If you are looking for an easy slow cooker beef dinner with tender steak, colorful vegetables, and a rich savory sauce, this Slow Cooker Pepper Steak with Bell Peppers is an excellent choice. Thin strips of beef are seasoned, quickly browned for extra flavor, then slowly cooked with onions, garlic, soy sauce, beef broth, and seasonings until tender and deeply flavorful.
Red, green, and yellow bell peppers add sweetness, freshness, and beautiful color, while sliced onions become soft and absorb the rich beef sauce. The combination of soy sauce, Worcestershire sauce, garlic, black pepper, and beef broth creates a glossy savory gravy that coats every strip of steak.
This slow cooker pepper steak is perfect for busy weeknights, family dinners, meal prep, or anytime you want comforting takeout-style flavor at home. Serve it over rice, noodles, mashed potatoes, or cauliflower rice for a satisfying complete meal.
Why You’ll Love This Slow Cooker Pepper Steak with Bell Peppers
The beef becomes tender and flavorful during slow cooking.
Browning the steak first creates richer flavor and helps the meat develop the caramelized appearance shown in the finished dish.
Colorful bell peppers provide sweetness, texture, and freshness.
Onions slowly soften and absorb the savory beef sauce.
The sauce is rich, garlicky, peppery, and perfect for spooning over rice.
Most of the cooking is hands-off once everything goes into the slow cooker.
The recipe can easily be customized with mushrooms, extra vegetables, ginger, chili flakes, or additional garlic.
Ingredients
For the Steak
- 2 pounds sirloin steak, flank steak, or chuck steak
- 1½ teaspoons kosher salt
- 1 teaspoon freshly ground black pepper
- 1 teaspoon garlic powder
- 1 teaspoon onion powder
- 1 teaspoon smoked paprika
- 2 tablespoons cornstarch
- 2 tablespoons olive oil
For the Bell Peppers and Onions
- 1 large red bell pepper, sliced into strips
- 1 large green bell pepper, sliced into strips
- 1 large yellow bell pepper, sliced into strips
- 2 medium yellow onions, sliced
- 5 garlic cloves, finely minced
For the Savory Pepper Steak Sauce
- 1½ cups low-sodium beef broth
- ⅓ cup low-sodium soy sauce
- 2 tablespoons Worcestershire sauce
- 1 tablespoon brown sugar
- 1 tablespoon tomato paste
- 1 tablespoon Dijon mustard
- 1 teaspoon sesame oil, optional
- 1 teaspoon freshly ground black pepper
- ½ teaspoon smoked paprika
- ½ teaspoon garlic powder
- ½ teaspoon onion powder
- ½ teaspoon dried thyme
- ¼ teaspoon crushed red pepper flakes, optional
For Thickening the Sauce
- 2 tablespoons cornstarch
- 2 tablespoons cold water
Optional Finishing Ingredients
- Sliced green onions
- Chopped fresh parsley
- Sesame seeds
- Extra freshly cracked black pepper
- Red pepper flakes
- Fresh cilantro
- Chili garlic sauce
How to Make Slow Cooker Pepper Steak with Bell Peppers
1. Prepare the Steak
Place the steak on a clean cutting board.
Trim away any large pieces of excess fat or tough connective tissue.
2. Slice the Beef
Slice the steak against the grain into strips approximately ½ inch thick and 2–3 inches long.
Cutting against the grain shortens the muscle fibers and helps the finished beef feel more tender.
3. Pat the Beef Dry
Use paper towels to thoroughly dry the steak strips.
Removing excess moisture allows the beef to brown instead of steaming in the skillet.
4. Season the Steak
Place the steak strips in a large bowl.
Season with:
- Salt
- Black pepper
- Garlic powder
- Onion powder
- Smoked paprika
Toss until evenly coated.
5. Add Cornstarch
Sprinkle approximately 2 tablespoons cornstarch over the seasoned beef.
Toss until every strip has a very light coating.
The cornstarch encourages browning and later helps give the sauce a slightly thicker texture.
6. Heat the Skillet
Place a large heavy skillet over medium-high heat.
Add approximately 1 tablespoon olive oil.
Allow the skillet to become very hot.
7. Brown the First Batch
Add half of the steak strips in a single layer.
Avoid overcrowding the skillet.
Cook for approximately 1–2 minutes without moving them excessively.
8. Turn the Beef
Flip or stir the steak.
Cook for another 1 minute.
The beef does not need to cook completely.
You are only creating browned edges.
9. Transfer to the Slow Cooker
Move the browned beef to the slow cooker.
10. Brown the Remaining Beef
Add the remaining olive oil if needed.
Repeat the browning process with the second batch.
Transfer it to the slow cooker.
11. Prepare the Onions
Slice the onions into thick strips.
Keeping the pieces slightly larger helps prevent them from completely disappearing during slow cooking.
12. Prepare the Bell Peppers
Remove the stems, seeds, and white membranes from the peppers.
Slice them into strips approximately ½ inch wide.
13. Add Some of the Onions
Scatter approximately half of the sliced onions over the beef.
Reserve the remaining onions for later if you prefer more texture.
14. Prepare the Garlic
Finely mince the garlic cloves.
Set aside while preparing the sauce.
15. Deglaze the Skillet
Return the skillet to medium heat.
Pour approximately ½ cup beef broth into the hot pan.
Use a wooden spoon or silicone spatula to scrape up all the browned bits.
16. Add the Garlic
Add the minced garlic.
Cook for approximately 30 seconds, stirring constantly.
17. Add the Tomato Paste
Stir in the tomato paste.
Cook for approximately 1 minute.
Briefly cooking tomato paste gives it a deeper, less raw flavor.
18. Add the Soy Sauce
Pour in the low-sodium soy sauce.
Stir thoroughly.
19. Add Worcestershire Sauce
Add the Worcestershire sauce.
This contributes additional savory depth.
20. Add Brown Sugar
Stir in the brown sugar.
The small amount of sweetness balances the salty and savory ingredients.
21. Add Dijon Mustard
Stir in the Dijon mustard.
It adds subtle tang and complexity without making the sauce strongly mustard-flavored.
22. Add the Remaining Broth
Pour in the rest of the beef broth.
Whisk until everything is evenly combined.
23. Add the Seasonings
Stir in:
- Black pepper
- Smoked paprika
- Garlic powder
- Onion powder
- Thyme
- Optional red pepper flakes
- Optional sesame oil
24. Simmer Briefly
Bring the sauce to a gentle simmer.
Cook for approximately 2–3 minutes.
25. Pour the Sauce Over the Beef
Carefully pour the sauce into the slow cooker.
Stir gently so the steak is evenly coated.
26. Cover the Slow Cooker
Place the lid securely on the slow cooker.
27. Cook on LOW
Cook on LOW for approximately 5–6 hours.
The exact time depends on the beef cut and your slow cooker.
28. Alternative HIGH Setting
You can cook the pepper steak on HIGH for approximately 2½–3½ hours.
LOW generally provides a more tender result.
29. Check the Beef
Toward the end of cooking, test one strip of beef.
It should be tender and easy to bite through.
If it still feels firm or chewy, continue cooking for another 30–60 minutes.
30. Add the Bell Peppers
Approximately 45–60 minutes before serving, add:
- Red bell pepper
- Green bell pepper
- Yellow bell pepper
Adding them near the end prevents them from becoming overly soft.
31. Add the Remaining Onions
If you reserved some onions, add them at the same time.
This creates a mixture of very soft onions and slightly firmer pieces.
32. Stir Gently
Fold the vegetables into the beef and sauce.
Cover again.
33. Continue Slow Cooking
Cook until the bell peppers are tender but still retain some shape and color.
This generally takes approximately 45 minutes on LOW or 20–30 minutes on HIGH.
34. Prepare the Cornstarch Slurry
In a small bowl, whisk together:
- 2 tablespoons cornstarch
- 2 tablespoons cold water
Mix until completely smooth.
35. Thicken the Sauce
Turn the slow cooker to HIGH.
Slowly stir the cornstarch slurry into the sauce.
36. Cook Until Thickened
Cover and cook for approximately 10–15 minutes.
The sauce should become glossy and thick enough to coat the beef and vegetables.
37. Adjust the Consistency
If the sauce is too thick, stir in a small splash of beef broth.
If it remains too thin, cook uncovered for another 5–10 minutes.
38. Taste the Sauce
Taste before adding additional salt.
Soy sauce and Worcestershire sauce already contribute plenty of seasoning.
Add extra:
- Black pepper
- Soy sauce
- Red pepper flakes
only if needed.
39. Coat the Beef
Gently stir the steak strips through the thickened sauce.
Make sure the peppers and onions are evenly distributed.
40. Add Fresh Black Pepper
For the classic pepper steak flavor, finish with another generous amount of freshly cracked black pepper.
41. Garnish
Top with any combination of:
- Green onions
- Parsley
- Sesame seeds
- Cilantro
- Red pepper flakes
42. Serve
Serve the pepper steak hot with plenty of savory sauce spooned over the beef, peppers, and onions.
What to Serve With Slow Cooker Pepper Steak with Bell Peppers
Pepper steak is especially delicious served over rice because the rice absorbs the flavorful sauce.
Serve it with:
- Steamed white rice
- Jasmine rice
- Brown rice
- Garlic butter rice
- Fried rice
- Cauliflower rice
It also pairs beautifully with:
- Egg noodles
- Lo mein noodles
- Rice noodles
- Mashed potatoes
- Roasted potatoes
- Quinoa
For vegetables, serve alongside:
- Steamed broccoli
- Green beans
- Bok choy
- Roasted asparagus
- Stir-fried vegetables
- Brussels sprouts
For a lower-carbohydrate meal, serve it over cauliflower rice, shredded cabbage, zucchini noodles, or simply enjoy it with extra vegetables.
Tips for the Best Slow Cooker Pepper Steak
Cut Against the Grain
Always slice beef across the visible muscle fibers.
This creates noticeably more tender strips.
Don’t Slice the Beef Too Thin
Very thin strips can become dry or fall apart during slow cooking.
Approximately ½ inch thick works well.
Brown the Beef in Batches
Crowding the skillet traps steam.
Smaller batches give the steak better caramelization.
Don’t Cook the Beef Completely While Searing
The slow cooker will finish cooking it.
The skillet step is only for developing flavor.
Use Low-Sodium Soy Sauce
The sauce concentrates during cooking, so regular soy sauce can make the final dish overly salty.
Add Bell Peppers Near the End
Cooking them for the entire slow-cooker period can make them extremely soft.
Adding them toward the end preserves better texture and color.
Use Several Pepper Colors
Red, green, and yellow peppers create the colorful appearance associated with classic pepper steak.
Add Plenty of Black Pepper
Freshly cracked pepper is one of the defining flavors of the dish.
Thicken the Sauce at the End
Slow cookers retain moisture, so thickening near the end gives better control over the final consistency.
Taste Before Adding Salt
Soy sauce, Worcestershire sauce, and beef broth can all contain significant sodium.
Easy Recipe Variations
Slow Cooker Mushroom Pepper Steak
Add 12 ounces sliced mushrooms during the final 60–90 minutes.
Spicy Pepper Steak
Add:
- 1 teaspoon red pepper flakes
- 1 tablespoon chili garlic sauce
- ½ teaspoon cayenne pepper
Adjust according to your preferred heat level.
Garlic Pepper Steak
Increase the garlic to 8 cloves.
Add another ½ teaspoon garlic powder.
Ginger Pepper Steak
Add 1 tablespoon freshly grated ginger with the garlic.
This gives the dish a fragrant Asian-inspired flavor.
Teriyaki Pepper Steak
Add:
- ¼ cup teriyaki sauce
- 1 teaspoon sesame oil
- 1 teaspoon fresh ginger
Reduce the soy sauce slightly.
Honey Garlic Pepper Steak
Add 2 tablespoons honey to the sauce.
This creates a slightly sweeter, stickier finish.
Pepper Steak With Pineapple
Add 1 cup pineapple chunks during the final 30 minutes.
The sweet acidity works especially well with peppers and savory beef.
Extra Vegetable Pepper Steak
Add:
- Mushrooms
- Snap peas
- Broccoli
- Carrots
during the final portion of cooking.
Onion Lovers’ Pepper Steak
Increase the onions to 3 large onions.
Extra Saucy Pepper Steak
Increase the beef broth to 2 cups and double the cornstarch slurry.
This is especially useful if serving the dish over plenty of rice.
Stovetop Method
You can also make pepper steak entirely on the stovetop.
Slice, season, and lightly coat the beef as directed.
Brown the steak in batches.
Transfer it temporarily to a plate.
Cook the onions and peppers in the same skillet for approximately 4–5 minutes.
Remove the peppers if you prefer them crisp.
Prepare the garlic and sauce in the skillet.
Return the beef.
Cover and simmer over low heat for approximately 15–20 minutes, or until tender.
Add the peppers back during the final 5 minutes.
Stir in the cornstarch slurry.
Simmer until the sauce becomes thick and glossy.
Serve immediately.
Make-Ahead Instructions
The steak can be sliced and seasoned up to 24 hours ahead.
Store it covered in the refrigerator.
The bell peppers and onions can also be sliced a day ahead.
Store them in separate airtight containers.
The savory sauce mixture can be prepared up to 3 days ahead.
Refrigerate until ready to cook.
For especially convenient meal preparation, brown the beef the evening before.
Cool it promptly and refrigerate.
The next morning, assemble everything in the slow cooker and cook as directed.
Wait until near the end to add the bell peppers.
How to Store Leftovers
Allow leftover pepper steak to cool.
Transfer it to an airtight container.
Refrigerate for up to 3–4 days.
Store the beef, peppers, onions, and sauce together.
Reheating on the Stovetop
Place the pepper steak in a skillet or saucepan.
Add approximately 1–2 tablespoons beef broth or water.
Cover and warm over low to medium-low heat until hot.
Reheating in the Microwave
Place an individual portion in a microwave-safe dish.
Cover loosely.
Microwave in short intervals, stirring between each interval.
Reheating in the Slow Cooker
For larger portions, return the leftovers to the slow cooker.
Heat on LOW until thoroughly warmed.
Do not leave reheated beef in the slow cooker for several additional hours because it can become overly soft.
Freezing
Slow cooker pepper steak freezes very well.
Allow everything to cool completely.
Transfer to freezer-safe airtight containers.
Freeze for up to approximately 2–3 months.
For the best vegetable texture, you can freeze the beef and sauce separately and add freshly cooked peppers after reheating.
Thaw overnight in the refrigerator.
Reheat gently on the stovetop.
If the sauce becomes too thick after freezing, add a small splash of beef broth.
Frequently Asked Questions
What type of beef is best for slow cooker pepper steak?
Sirloin, flank steak, chuck steak, or round steak can all work. Chuck is especially suitable for longer cooking, while sirloin generally needs less time.
Should I sear the beef first?
It is not strictly necessary, but browning greatly improves the flavor and appearance.
Why is my pepper steak tough?
The beef may either need additional cooking time or may have been sliced with the grain rather than against it.
When should I add bell peppers to the slow cooker?
Add them during approximately the final 45–60 minutes on LOW so they remain tender without becoming mushy.
Can I add the peppers at the beginning?
Yes, but they will become very soft and may lose much of their color.
Can I use frozen bell peppers?
Yes. Add them during the final 30–45 minutes because frozen peppers soften quickly.
Can I use chicken instead of beef?
Yes, although the cooking time should be reduced because chicken cooks much faster.
Why is my sauce watery?
Slow cookers trap moisture. Stir in a cornstarch slurry near the end and cook on HIGH until thickened.
Can I double the recipe?
Yes, provided your slow cooker is large enough and is not filled beyond approximately two-thirds to three-quarters capacity.
Can I make this recipe spicy?
Absolutely. Add crushed red pepper flakes, cayenne, chili garlic sauce, or sliced jalapeños.
Final Thoughts
This Slow Cooker Pepper Steak with Bell Peppers combines tender strips of beef, colorful peppers, softened onions, garlic, soy sauce, Worcestershire sauce, black pepper, and rich beef broth in one comforting slow cooker meal.
The key is slicing the beef against the grain, browning it before slow cooking, adding the bell peppers near the end so they retain their color and texture, and thickening the cooking liquid into a glossy savory sauce before serving.
Serve the pepper steak generously over rice, noodles, potatoes, or cauliflower rice for an easy family dinner packed with tender beef, sweet peppers, savory onions, and bold peppery flavor.