Position 1 oven rack in the center and the second rack on the bottom of the oven and preheat to 450 degrees F. Sprinkle the cornmeal over 2 rimless baking sheets. Roll out each piece of pizza dough into a 10 to 11-inch round. Transfer 1 dough to each prepared baking sheet.
Spoon the marinara sauce
over the dough, dividing equaling and leaving a 1-inch border around each pizza. Sprinkle the cheeses over the sauce. Arrange the pineapple pieces in a single layer over the cheeses. Sprinkle with the ham
. Bake the pizzas until the crusts are crisp
and brown on the bottom and the cheese
is melted on top, about 12 minutes. Cut the pizza into wedges and serve immediately.