Instructions:
- Prepare the Beef: Start by slicing the beef sirloin into thin strips, about 1/4 inch thick. Pat the beef dry with paper towels to remove excess moisture, which will help with browning.
- Coat the Beef: In a bowl, combine the soy sauce, minced garlic, brown sugar, tomato paste, ground ginger, red pepper flakes (if using), salt, and black pepper. Mix well until the sugar is dissolved. Pour this marinade over the sliced beef in a large bowl. Toss the beef to ensure it’s evenly coated. Cover the bowl with plastic wrap and let it marinate in the refrigerator for at least 30 minutes. You can also leave it overnight for a deeper flavor.
- Sear the Beef: Heat a skillet or frying pan over medium-high heat. Add one tablespoon of vegetable oil to the pan. Once the oil is hot, add the marinated beef strips in batches, making sure not to overcrowd the pan. Sear the beef for about 1-2 minutes per side until it gets a nice brown color. Transfer the seared beef to your crockpot.
- Prepare the Vegetables: In the same skillet, add the remaining tablespoon of vegetable oil. Sauté the sliced onions and bell peppers for 3-4 minutes until they start to soften. Transfer the sautéed vegetables to the crockpot with the beef.
- Combine and Cook: Pour the beef broth into the crockpot, covering the beef and vegetables. Stir gently to combine everything. Cover the crockpot with its lid.
- Crockpot Cooking: Set the crockpot to cook on low heat for 6-8 hours or on high heat for 3-4 hours. This slow cooking method will allow the flavors to meld together and make the beef tender.
- Thicken the Sauce: About 30 minutes before serving, take out about 1/4 cup of the liquid from the crockpot and whisk it with cornstarch until smooth. Pour this cornstarch mixture back into the crockpot and gently stir. Cover and allow the sauce to thicken.
- Serve: Once the sauce has thickened to your desired consistency, turn off the crockpot. Serve the pepper steak over cooked rice or noodles. Garnish with chopped green onions or sesame seeds if desired.
This Crockpot Pepper Steak recipe yields tender, flavorful beef with savory sauce and colorful vegetables—a perfect meal for a cozy dinner at home. Adjust the seasoning according to your taste preferences and enjoy!