Cook the Chicken:
Heat 1 tablespoon of olive oil in a large skillet over medium-high heat.
Add the chicken, season with garlic powder, onion powder, salt, and pepper, and cook until golden and cooked through. Remove and set aside.

Sauté Veggies:
In the same skillet, add the remaining olive oil. Sauté onions, bell peppers, and mushrooms until soft and slightly caramelized, about 6–8 minutes.

Combine:
Return the cooked chicken to the skillet with the veggies. Mix well and reduce heat to low.

Add Cheese:
Sprinkle cheese evenly over the mixture. Cover the skillet with a lid and let the cheese melt, about 2–3 minutes.

Serve:
Scoop into bowls or stuff into hoagie rolls for a cheesy, skillet-style take on the Philly classic!