Slow-Cooker Pepper Steak: Tender Beef With Peppers and Savory Sauce

Slow-Cooker Pepper Steak combines tender strips of beef, colorful bell peppers, onions, garlic, and a rich savory sauce in an easy slow-cooker dinner. A combination of beef broth, soy sauce, Worcestershire sauce, tomato paste, brown sugar, and seasonings creates plenty of flavor while the beef slowly becomes tender.

This recipe works with beef sirloin, round steak, or chuck steak, so you can choose the cut that fits your preference. Although browning the beef before slow cooking remains optional, a quick sear adds another layer of flavor.

After several hours, a simple cornstarch slurry transforms the cooking liquid into a thick, glossy sauce. Serve Slow-Cooker Pepper Steak over rice, mashed potatoes, or cauliflower rice to capture every spoonful.

Prep takes about 15 minutes, while the slow cooker handles the rest.

I especially like this type of dinner on days when I want something hearty without spending the evening standing over the stove. I can slice everything, load the slow cooker, and leave most of the cooking alone. When I have a few extra minutes, I brown the beef first because the seared edges add a noticeable savory flavor. However, I’ve also skipped that step on busy days and still ended up with a satisfying meal. The final cornstarch step makes the biggest visual difference. The thin cooking liquid quickly turns into a shiny sauce that coats the beef and peppers instead of disappearing into the rice underneath.

Preparing the Beef and Vegetables

Slice and Season the Beef

Start with 2 pounds beef sirloin, round steak, or chuck steak.

Slice the beef into thin strips against the grain.

Cutting against the grain shortens the long muscle fibers, which works particularly well for strips of steak.

Next, season the beef with ½ teaspoon black pepper, 1 teaspoon smoked paprika, and ½ teaspoon onion powder.

Toss the strips gently so the seasoning reaches the beef evenly.

Meanwhile, slice 2 large bell peppers and 1 large onion.

Mince 3 cloves garlic and set everything aside.

Because Slow-Cooker Pepper Steak uses relatively simple ingredients, preparing everything before assembling the slow cooker keeps the process quick and organized.

Brown the Beef for Extra Flavor

Heat 1 tablespoon olive oil in a skillet over medium-high heat.

Working in batches, quickly brown the beef strips.

Avoid overcrowding the skillet. Too much beef at once can release enough moisture to prevent effective browning.

You don’t need to cook the strips completely. Instead, give the exterior a quick sear and then transfer the beef to the slow cooker.

This browning step remains optional. Therefore, if you’re short on preparation time, you can place the seasoned beef directly into the slow cooker.

Either method works with the long cooking process. However, searing creates additional browned flavor before the sauce goes into the cooker.

Building the Pepper Steak and Savory Sauce

Layer the Peppers, Onion, and Beef

Add the sliced onion and 2 sliced bell peppers to the slow cooker.

Spread the vegetables across the bottom.

Next, place the seasoned beef strips over the vegetables.

Sprinkle the 3 minced garlic cloves over the beef.

This simple layering method keeps assembly easy while distributing the main ingredients throughout the cooker.

As Slow-Cooker Pepper Steak cooks, the onions and peppers release moisture while absorbing flavor from the seasoned cooking liquid.

You don’t need to add the cornstarch yet. Save it until the final portion of the cooking time so you can control the thickness of the finished sauce.

Mix the Savory Slow-Cooker Sauce

Pour 1 cup beef broth into a mixing bowl or large measuring cup.

Add ½ cup low-sodium soy sauce, 2 tablespoons Worcestershire sauce, 1 tablespoon tomato paste, and 1 tablespoon brown sugar.

For optional heat, add ¼ teaspoon red pepper flakes.

Whisk until the tomato paste and brown sugar become evenly incorporated.

Pour the mixture over the beef, peppers, onions, and garlic.

The soy sauce and Worcestershire provide the primary savory flavors, while the tomato paste adds richness. Meanwhile, the small amount of brown sugar balances the stronger salty and savory ingredients.

Cover the slow cooker once everything is assembled.

Slow Cooking and Thickening the Pepper Steak

Cook Until the Beef Is Tender

Cook Slow-Cooker Pepper Steak on LOW for 6 to 7 hours.

Alternatively, cook it on HIGH for approximately 3 to 4 hours.

The beef should become tender during the long cooking period.

Since different beef cuts and slow cookers can behave differently, use the suggested cooking times as a practical range rather than depending only on the clock.

Keep the lid closed as much as possible during cooking.

The sauce will remain relatively thin for most of the cooking process. That’s expected because you’ll thicken it near the end rather than adding cornstarch at the beginning.

Make the Sauce Thick and Glossy

During the final 15 to 20 minutes, combine 2 tablespoons cornstarch and 3 tablespoons cold water in a small bowl.

Stir until completely smooth.

Then pour the slurry into the slow cooker and stir it gently into the cooking liquid.

Turn the slow cooker to HIGH if necessary.

Cover and continue cooking for another 15 to 20 minutes.

As the liquid heats with the cornstarch, it should gradually thicken into a glossy sauce that coats the strips of beef and vegetables.

Before serving, gently stir the Slow-Cooker Pepper Steak so the sauce distributes evenly throughout the cooker.

Serving and Storing Slow-Cooker Pepper Steak

Serve With Rice or Potatoes

Serve the pepper steak hot.

Rice makes a natural base because it absorbs the savory sauce while keeping the beef and peppers at the center of the meal.

However, mashed potatoes also work well with the thickened sauce.

For another option, serve the beef and vegetables over cauliflower rice.

Spoon plenty of sauce over each portion rather than draining the beef and vegetables.

The glossy cooking sauce is an important part of Slow-Cooker Pepper Steak, especially after the cornstarch thickens it during the final few minutes.

With beef, peppers, and onions already included, you can keep additional sides simple.

Save the Leftovers With the Sauce

If you have leftovers, store the beef, peppers, onions, and sauce together in a covered container in the refrigerator.

Keeping everything together helps the meat stay coated in the flavorful sauce.

When reheating, warm the pepper steak gently until heated through.

The cornstarch-thickened sauce may become thicker after refrigeration. Therefore, if needed, stir in a small splash of beef broth or water while reheating.

Leftover Slow-Cooker Pepper Steak also works well for another rice bowl the next day.

Simply prepare fresh rice, warm the beef and vegetables, and spoon the reheated sauce generously over the top.

Ingredients

• 2 pounds beef sirloin, round steak, or chuck steak, thinly sliced
• 2 large bell peppers, sliced
• 1 large onion, thinly sliced
• 3 cloves garlic, minced
• 1 cup beef broth
• ½ cup low-sodium soy sauce
• 2 tablespoons Worcestershire sauce
• 1 tablespoon tomato paste
• 1 tablespoon brown sugar
• 1 teaspoon smoked paprika
• ½ teaspoon black pepper
• ½ teaspoon onion powder
• ¼ teaspoon red pepper flakes, optional
• 1 tablespoon olive oil
• 2 tablespoons cornstarch
• 3 tablespoons cold water

Instructions

1. Slice the beef into thin strips against the grain. Season with black pepper, smoked paprika, and onion powder.
2. Heat the olive oil in a skillet over medium-high heat. Working in batches, quickly brown the beef for extra flavor. Skip this step if desired.
3. Add the sliced bell peppers and onion to the slow cooker. Place the beef on top and add the minced garlic.
4. Whisk together the beef broth, low-sodium soy sauce, Worcestershire sauce, tomato paste, brown sugar, and optional red pepper flakes.
5. Pour the sauce over the beef and vegetables. Cover and cook on LOW for 6 to 7 hours or HIGH for 3 to 4 hours, until the beef becomes tender.
6. During the final 15 to 20 minutes, stir the cornstarch and cold water together until completely smooth.
7. Stir the cornstarch slurry into the slow cooker. Cook on HIGH for another 15 to 20 minutes, until the sauce becomes thick and glossy.
8. Gently stir and serve hot over rice, mashed potatoes, or cauliflower rice.

Frequently Asked Questions

What beef works best for Slow-Cooker Pepper Steak?

You can make this recipe with beef sirloin, round steak, or chuck steak. Slice whichever cut you choose into thin strips against the grain.

Do I have to brown the beef first?

No. Browning remains optional. However, quickly searing the beef in olive oil before slow cooking adds another layer of savory flavor.

When should I add the cornstarch?

Add the cornstarch slurry during the final 15 to 20 minutes. Mix the cornstarch with cold water first, then stir it into the hot cooking liquid.

Can I make Slow-Cooker Pepper Steak spicy?

Yes. Add the optional ¼ teaspoon red pepper flakes to the sauce. You can omit them when you want a milder dinner.

What should I serve with pepper steak?

Rice, mashed potatoes, and cauliflower rice all work well because they pair easily with the beef, vegetables, and thick savory sauce.

Conclusion

Slow-Cooker Pepper Steak makes a hearty beef dinner with straightforward preparation and plenty of savory sauce.

Thin strips of sirloin, round steak, or chuck steak cook with bell peppers, onions, and garlic. Meanwhile, beef broth, low-sodium soy sauce, Worcestershire sauce, tomato paste, brown sugar, and seasonings create the flavorful cooking liquid.

You can quickly brown the beef before slow cooking for additional flavor or skip the searing step when you need faster preparation.

After 6 to 7 hours on LOW or 3 to 4 hours on HIGH, finish Slow-Cooker Pepper Steak with a simple cornstarch slurry. In just 15 to 20 minutes, the cooking liquid becomes a thick, glossy sauce that’s perfect for spooning over rice, mashed potatoes, or cauliflower rice.