Preheat oven with pizza stone on lower middle rack to 500°F for at least 30 minutes, preferably 1 hour. Meanwhile, prepare the toppings.
Heat olive oil in a saucepan over medium/high heat. Add the green pepper and saute for 3 minutes, then and half of the chopped onion (equivalent of 1/4 onion) and saute until softened, about 3-5 minutes. Transfer mixture to a small bowl and set aside.
Using the same pan, brown the sausage and crumble into small pieces. Cook through and transfer to a plate lined with paper towels to drain grease.
Roll out dough into a large circle, approximately 14 inches in diameter, on a piece of parchment paper. If you do not have parchment paper, generously apply cornmeal to a large surface, such as a cutting board, and roll out the dough. The cornmeal is essential to eventually sliding the pizza directly onto the pizza stone if not using parchment paper.
Top pizza in the following order: sauce, pepperoni, bacon, sausage, grilled pepper/onion mixture, remaining raw onions, mozzarella cheese, grated Parmesan cheese, then a sprinkle of Pizza/Italian seasoning.
If using parchment paper, use a pizza peel or a flat baking sheet to transfer the pizza and parchment onto the baking stone in the oven. If using cornmeal, remove hot pizza stone from oven, apply extra cornmeal to the surface of the stone, and slip pizza directly onto stone.
Bake for 8-12 minutes, or until cheese is melted as desired.
Remove pizza from oven, slide onto a large cutting board and slice.