Vegetable Calzones

• 1 pound pizza dough, at room temperature
• 2 tablespoons olive oil 
• 1 small onion, thinly sliced  (optional if you do not like onions)
• 1 small bell pepper, any color, seeded and sliced
• Salt and pepper
• 8 ounces chopped mushrooms 
• 1 cup jarred pasta sauce  (I use my own sauce)
• 1/2 cup pitted, sliced ripe olive
• sprinkle each with a little oregano and garlic
• 2 cups shredded mozzarella
• 1/2 cup grated Parmesan  or Pecorino Romano cheese  (I have also used Asiago)

Preparation

1. 1. Preheat oven to 375°F. Quarter pizza dough; cover. Dust a baking sheet with flour. Warm 1 Tbsp. oil in a skillet over medium heat. Add onion and bell pepper, season with salt and pepper and sauté until tender, about 5 minutes. Remove to a bowl. Warm 1 Tbsp. oil in skillet. Sauté mushrooms until they give up their liquid, about 4 minutes. Add to bowl; stir.
2. 2. Roll each piece of dough into an 8-inch circle. Spread 1/4 cup sauce onto each round, leaving a 1/2-inch border. Divide vegetables and olives among rounds; sprinkle a little oregano and garlic, and some Parmesan or Romano cheese,  then with  mozzarella.
3. 3. Fold rounds in half, pressing to seal. Sprinkle  top of calzones with a little pepper and Parmesan. Transfer to baking sheet and bake 15 to 20 minutes, until golden brown. Serve.