Spinach and Red-Pepper Calzones
No need to call your local pizza joint. Thanks to prepared dough and bottled roasted red peppers, making your own calzones can be easy and far more satisfying.
1 1/2 tablespoons cornmeal
1 large onion, halved and sliced lengthwise
3 tablespoons extra-virgin olive oil, divided
2 garlic cloves, finely chopped
5 ounces baby spinach (8 packed cups)
4 bottled roasted red peppers, rinsed, patted dry, and cut into 1-inch pieces (1 cup)
12 oil-cured black olives, pitted and coarsely chopped (about 3 tablespoons)
1 pound store-bought pizza dough, thawed
1/2 pound smoked mozzarella, cut into 16 pieces
Preheat oven to 500°F with rack in lowest position. Sprinkle cornmeal on a large baking sheet.
Cook onion with 1/4 teaspoon salt in 2 tablespoons oil in a large heavy skillet over medium heat, stirring occasionally, until beginning to brown, 8 to 10 minutes. Add garlic and cook until fragrant, about
1 minute. Add spinach and cook, stirring frequently, until wilted, about 2 minutes. Stir in red peppers, olives, and pepper to taste. Remove from heat.
Roll out dough on a lightly floured surface with a lightly floured rolling pin into a 14-inch round, then cut into quarters. Roll out 1 quarter into an 8-inch square (keep remaining pieces covered) and arrange with a corner nearest you. Put one fourth of filling on lower half, leaving a 1-inch border, and top with 4 pieces of cheese. Fold dough over to enclose filling. Seal edges. Beginning in 1 corner, stretch sealed edge outward, pinching and rolling dough up over edge to resemble a rope, working your way around. Transfer to baking sheet. Make 3 more calzones in same manner. Cut 3 steam vents in top of each and brush with remaining tablespoon oil.
Bake until golden-brown, 13 to 15 minutes. Cool 5 minutes before serving.
Cooks' note:
Filling (without cheese) can be made 1 day ahead and chilled. Bring to room temperature before using.