Prep the Ingredients: Season the ButcherBox Premium Steak Tips with salt and pepper. Slice the onion, bell peppers, and mushrooms. Preheat a large skillet over medium-high heat.
Cook the Steak Tips: Heat 1 tablespoon of olive oil in the skillet. Add the steak tips and sear for about 2-3 minutes per side, or until browned and cooked to desired doneness. Remove the steak tips from the skillet and set aside, covering to keep warm.
Sauté the Vegetables: In the same skillet, add the remaining tablespoon of olive oil. Add the onions, bell peppers, and mushrooms. Sauté for about 5-7 minutes, or until the vegetables are soft and lightly caramelized. Season with salt, pepper, and optional garlic powder and red pepper flakes to taste.
Assemble the Subs: Slice the sub rolls open and distribute the cooked steak tips evenly among them. Top with the sautéed vegetable mixture. Place two slices of provolone cheese over the top of the vegetables on each sub.
Melt the Cheese: Place the open-faced subs under a preheated broiler for 2-3 minutes, or until the cheese is melted and bubbly. Watch carefully to avoid burning.
Serve: Close the subs, pressing down gently to compact the fillings. Serve immediately for the best experience.