Prep the vegetables. Slice the onion and peppers into thin strips. Mince the garlic. Keep everything close by so the skillet moves fast.
Sauté the peppers and onions. Heat oil in a large skillet over medium-high heat.
Add onions and peppers with a pinch of salt. Cook, stirring occasionally, until softened and lightly browned, about 7–9 minutes. Transfer to a plate.
Brown the turkey. In the same skillet, add the ground turkey.
Break it up with a spatula and cook until no longer pink, 5–6 minutes. Don’t over-stir; let it get some browning for flavor.
Season it well. Stir in garlic, steak seasoning, garlic powder, onion powder, and Worcestershire sauce. Cook 1–2 minutes until fragrant.
Deglaze and simmer. Pour in the broth to loosen brown bits from the pan.
Simmer 2–3 minutes until slightly reduced.
Bring it together. Return peppers and onions to the skillet. Toss to combine. Taste and adjust with salt and pepper.
If using mushrooms or banana peppers, stir them in now.
Cheese it up. Reduce heat to low. Lay provolone slices over the mixture, slightly overlapping. Cover and let the cheese melt, 1–2 minutes.
If using shredded cheese, sprinkle evenly and cover until melted and gooey.
Serve your way. Spoon into toasted rolls for a cheesesteak-style sandwich, or serve over rice, cauliflower rice, or crispy potatoes. Add hot sauce or a sprinkle of red pepper flakes if you like heat.