Heat 1 teaspoon olive oil over medium heat in a large skillet. Add garlic and onion. Sauté until browned, about 1 minute. Add spinach. Cook until wilted, about 2 minutes, stirring occasionally.
Combine ricotta, mozzarella, eggs, salt, and pepper. Set aside.
Preheat oven to 425.
Grease 2 12 inch cast iron skillets or cake pans. Sprinkle with cornmeal (optional) or line with parchment. Press dough onto bottom and up sides of pans.
Spread half the sauce onto the dough on the bottoms of each pan. Using the back of a spoon, spread to the edges. Top each with 1/2 the spinach mixture, 1/2 the ricotta mixture, and 1/2 the parmesan.
Bake at 425 for 20 minutes or until crust is beginning to brown and filling is melty and bubbly. Let stand 15 minutes before cutting.