Roasted Root-Vegetable Pizza

Preheat oven to 475 degrees, with racks in upper and lower thirds. Brush a large rimless baking sheet with oil. Gently stretch dough into 12-by-16-inch oval (or as large as will fit on baking sheet); transfer to prepared sheet.

Sprinkle dough evenly with half the mozzarella. Scatter vegetables on top, then dollop with ricotta; sprinkle with remaining mozzarella and the rosemary, if desired. Drizzle with oil; season with salt and pepper. Bake rotating sheet from top to bottom and front to back halfway through, until crust is golden, 20 to 25 minutes.