Squash and Potato Pizzas

Name: Squash and Potato Pizzas
Ingredients: 1 pound medium red or Yukon Gold potatoes, scrubbed well but not peeled; 3 tablespoons extra-virgin olive oil, plus more for drizzling; 1 pound medium yellow squash, sliced lengthwise 1/8 inch thick; Salt and freshly ground pepper; All-purpose flour, for dusting; 1 1/2 pounds thawed frozen pizza dough, cut into 4 pieces; 24 cherry tomatoes, coarsely chopped (1 cup); 2 1/2 cups Manchego cheese (7 1/2 ounces), shredded; 2 ounces frisée, torn into large pieces (optional)