Remove the meat mixture from the heat. Divide the pizza dough into 4 equal pieces (one for each serving). Roll each piece out to about 1/4 inch thick, aiming for an oval or round shape.
Spoon a generous amount of the filling onto one half of each dough piece, leaving a border around the edge. Fold the dough over the filling and firmly crimp or roll the edges to seal. Cut a few slits in the top of each calzone to allow steam to escape while baking. For a richer golden crust, you can brush the tops with a little egg white before baking.
Bake in a preheated oven at 425°F for 15 to 20 minutes, or until the tops are a deep golden brown. If you have a pizza stone, baking on a preheated one will help ensure a crisp bottom crust.