Allow pizza dough to rise and double in size. Preheat oven to 450°F.
Melt butter in pan, cut thin steak into strips and saute in a frying pan with vegetables until cooked through. Sprinkle onion powder over meat and veggies (to taste); set aside.
Roll out pizza dough, brush bottom of pan with olive oil and spread dough on pizza pan. Spread a THIN layer of beef gravy over the dough. Place provolone cheese over the gravy. Shred the roast beef over the cheese; add American cheese slices on roast beef. Add the steak & veggie mix to the top of the pizza. Cover with mozzarella cheese.
Bake in oven about 10 min until the bottom of crust is golden brown. When pizza comes out of the oven let it stand about 5-8 minutes, so the cheese can settle.