On a lightly floured surface, divide dough into four equal pieces. Roll or stretch each piece into a 6-inch round. If dough shrinks back, let rest about 5 minutes, then roll again.
In a bowl, mix ricotta, mozzarella, and garlic. Add salt and pepper to taste.
Place about 3 tablespoons ricotta mixture and about 2 tablespoons pasta sauce in the center of each round of dough. Top with about 1/4 cup vegetables and about 3 tablespoons meat.
Fold rounds in half over filling, making a half-moon shape. Press edges of dough with the tines of a fork to seal. Brush tops of calzones lightly with olive oil. Place slightly apart on a lightly oiled baking sheet.
Bake in a 450° oven until golden brown, 15 to 20 minutes. Let cool about 10 minutes on baking sheet, then transfer to plates.