Preheat oven to 375°F (190°C). Set out ingredients for smooth preparation.
Dust counter with flour and roll dough to 12×18 inches.
Sauté onion and pepper in olive oil until soft, then set aside.
Spread sausage, vegetables, pepperoni, cheeses, and seasonings over dough.
Roll dough tightly, seal edges, ready for baking.
Bake seam-side down at 375°F for 25-30 minutes until golden brown.
Let cool, slice, and serve with marinara sauce.
