Slice and prep. Pat the steak dry and season with salt, pepper, onion powder, garlic powder, paprika, and oregano.
Set aside while you prep the vegetables.
Cook the veggies. Heat 1 tablespoon oil in a large skillet over medium-high heat. Add onions and peppers with a pinch of salt. Cook 6–8 minutes, stirring now and then, until softened and lightly browned.
If using mushrooms, add them in the last 3–4 minutes. Transfer veggies to a plate.
Sear the steak. Add remaining oil to the skillet. Increase heat to high.
Add the steak in a single layer (work in batches if needed). Sear 1–2 minutes per side until just cooked through and browned on the edges.
Build flavor. Reduce heat to medium. Add butter and minced garlic to the skillet with the steak.
Stir until the garlic is fragrant, about 30 seconds. Add Worcestershire and coconut aminos (if using). Toss to coat.
Combine. Return the veggies to the pan and toss with the steak.
Taste and adjust salt and pepper. You want it well-seasoned and slightly saucy.
Add the cheese. Turn off the heat. Lay provolone slices over the mixture.
Cover the pan for 1–2 minutes so the cheese melts. Alternatively, fold shredded cheese through until melty.
Portion. Divide evenly into 3–4 meal prep containers. Spoon any pan juices over the top for extra flavor.
Garnish with parsley if you like.
Cool, then store. Let containers cool uncovered for 10–15 minutes before sealing to avoid condensation.