Place meat, onion and garlic in a skillet over medium heat. Cook until beef is evenly browned. Drain off grease. Season the meat with chili powder, cumin, paprika, salt, and pepper.
Coat 2 pie plates with non-stick cooking spray. Place one tortilla in each pie plate and cover with a layer of refried beans. Spread half of the seasoned meat over each tortilla and then cover with a second tortilla. Bake for 10 minutes in the preheated oven. Remove from the oven and allow to cool slightly.
Spread half of the salsa over the top tortillas. Top each pizza with half of the cheese, tomatoes, green onions, and olives. Return the pizzas to the oven, bake until the cheese is melted, about 5 to 10 minutes. Remove from the oven and allow to cool slightly. Slice each pizza into 4 pieces and serve.