Arrange oven racks in the lower and upper thirds of the oven. Heat oven to 475° F.
Divide the dough into four equal portions. Roll out on a well-floured surface to make four 6-inch rounds. Transfer to two ungreased baking sheets.
Combine the sirloin with the garlic, cinnamon, and allspice, and season with salt and pepper.
Crumble the sirloin evenly over each round. Top with the oregano, onion, and tomatoes.
Bake 10 minutes. Remove the pizzas from the oven and scatter Feta on top.
Return pizzas to oven and bake 5 minutes longer, or until the edges are lightly browned and the beef is thoroughly cooked.