How to Make It
Preheat the oven to 450°. Brush a large ceramic baking dish with olive oil. In a large bowl, whisk the egg. Stir in the panko, garlic, parsley, 1/4 cup of the cheese, 1 teaspoon of salt and 1/2 teaspoon of pepper. Add the ground beef and gently knead to combine. Form the mixture into 1-inch meatballs and transfer to the baking dish. Bake for about 10 minutes, turning once, until browned.
Meanwhile, in a large saucepan, heat the 1 tablespoon of olive oil. Add the crushed tomatoes and cook over moderately high heat until bubbling.
Add the meatballs to the tomato sauce, cover partially and simmer over moderately low heat until the meatballs are cooked through, about 10 minutes. With a large spoon, mash the meatballs into large chunks. Remove from the heat.
Meanwhile, brush 2 large baking sheets with olive oil and preheat in the upper and lower thirds of the oven. On a lightly floured work surface, cut each ball of dough in half. Roll each piece into a 10-inch oval. Arrange the dough on the heated baking sheets. Bake for about 7 minutes, shifting the pans halfway through baking, until lightly golden on top.
Spread the meatball sauce over the crusts, leaving a 1/2-inch border around the rims. Sprinkle with the remaining 3/4 cup of cheese. Bake for about 5 minutes, until the crust is crisp on the bottom and the cheese is melted. Scatter basil leaves over the pizzas and serve hot.