2tspsteak seasoningdivided [i.e. Mesquite/Montreal/Chicago/ Kansas City your preference]
1red bell pepperseeded and sliced
1green bell pepperseeded and sliced
1largesweet onioncut into thin wedges
Black pepper to taste
Use a sharp knife to cut sirloin steaks into 1-inch pieces.
Marinade: In a small bowl whisk together the teriyaki sauce, brown sugar, olive oil, chopped parsley, 3 clove minced garlic and red pepper flakes. Place into a plastic storage bag and refrigerate for several hours or overnight.
Prepare: Remove the sirloin tips from the marinade. Discard the marinade.
Heat a few drizzles of olive oil in a large cast iron or heavy skillet over medium-high heat. Add the sirloin tips. Cook for 5-7 minutes until browned and to your preferred doneness. Season with 1 tsp of steak seasoning. Remove from the pan to a platter to rest.
To the skillet add the sliced bell peppers and onion wedges. Season with 1 tsp steak seasoning and black pepper to your taste. Add additional olive oil if needed.
Cook for 5 minutes scraping the brown bits from the bottom of the skillet. Cook until browned and crisp tender.
Add the sirloin beef tips back to the pan. Stir until heated through then serve.
Steak seasonings vary in sodium content. Adjust the amount to your taste based on the particular brand used.