Freeze the pizza dough and roast the tomatoes in advance to cut down on prep time for this perfect weeknight meal.
Stretch and roll out two 1-pound balls of pizza dough (thawed if frozen) to 14-inch ovals. Place on 2 baking sheets and freeze until firm, about 1 1/2 hours. If making ahead, wrap crusts in plastic and freeze for later use.
Preheat oven to 350 degrees. Halve 14 plum tomatoes. On 2 large rimmed baking sheets, arrange tomatoes, cut side up, and sprinkle with 1/4 teaspoon sugar. Bake until softened and edges are crinkled, about 1 hour. If making ahead, let cool, then cover and refrigerate.
Heat oven to 475 degrees, with racks in upper and lower thirds. Lightly oil 2 large baking sheets. Place frozen or just-made crusts on sheets and brush each with 1 tablespoon oil.
Top one crust with tomatoes, dollop with ricotta, then sprinkle with Parmesan; season with salt and pepper. Top second crust with an even layer of potatoes, sprinkle with rosemary, then drizzle with 1 tablespoon oil; season with salt and pepper.
Bake pizzas until crusts are browned, about 11 minutes, rotating sheets halfway through. Sprinkle ricotta-tomato pizza with basil.
This recipe makes a double batch of pizza, so you can feed a crowd tonight -- or enjoy leftovers for lunch tomorrow.