Lay pizza dough on a lightly floured surface so it can rest.
Slice Italian sausage into ½ inch slices; fry in a 10" skillet over medium heat until browned, about 10 minutes.
Add ½ cup water, peppers and onions; bring to boil and cover.
Reduce heat to low and cook about 5-10 minutes more, or until veggies are tender and sausage is heated through.
Drain liquid from skillet and sprinkle sausage mixture with Italian seasoning; set aside.
Preheat oven to 375 degrees and spray a baking sheet with cooking spray.
Roll pizza dough (on a lightly floured counter) into a rectangle, approximately 11 x 17.
Sprinkle with sausage mixture, then the cheeses.
Start at the bottom of the long side and roll jellyroll fashion, stopping occasionally to stuff sides it. When you get to the end, pinch seam together, trying to squeeze air out as you go.
Place seam side down on baking sheet; bake for about 25 minutes at 375 degrees.
Remove from oven and lay a clean dish towel on top of loaf; this will allow the crust to soften up and it will be easier to slice and eat.
After about 10 minutes or so, slice into 1 inch slices. Serve with warmed sauce for dipping, if desired.