Turn the oven to broil.
Place the pepper on a baking sheet and place it under the broiler, about 6 inches from the element. Turn it as it gets blackened remove from oven. (The entire pepper does not need to be black.) Place in a plastic bag for 10 minutes. Let sweat. Peel off the skin. Cut into long thin strips.
Roll out the dough. Place the dough on an oiled pizza pan or baking sheet. Or, on a pizza peel with a little flour and cornmeal to move pizza to a stone or tile. Brush olive oil over the entire pizza. Place spinach in one layer. Lay the mushrooms on top of the spinach evenly dispersed. Disperse roasted red peppers evenly.
Sprinkle lightly with coarse salt and fresh ground black pepper. Drizzle on a little more olive oil very lightly. Add the sausage, if using. Sprinkle on the Provolone cheese dispersed evenly.
Bake in a 500 degree oven for 6-8 minutes on bottom oven rack until crisp.