Begin by gathering all your ingredients. Slice the round steak thinly against the grain for optimal tenderness. Mince the garlic, chop the tomatoes, and cut the green peppers into strips.
In a bowl, combine the sliced steak with soy sauce, minced garlic, ginger, and black pepper. Let it marinate for at least 15 minutes to allow the flavors to meld.
In a large skillet or wok, heat the olive oil over medium-high heat. Once hot, add the marinated steak to the skillet. Sear the steak for about 3-4 minutes, stirring occasionally until browned.
Add the green peppers and chopped tomatoes to the skillet. Stir-fry for an additional 5 minutes until the vegetables are tender but still crisp.
Pour in the beef bouillon (or broth) and add the sugar. Bring the mixture to a simmer, allowing the flavors to combine for about 2 minutes.
Stir in the cornstarch slurry gradually. Continue to cook for another minute until the sauce thickens to your desired consistency. Adjust seasoning if necessary.
Remove from heat and serve your delicious pepper steak over steamed rice, noodles, or even on its own. Enjoy the burst of flavors in every bite!
