Mexican Pizza

Preheat oven to 375° and line a medium baking sheet with parchment paper. Heat a large skillet over medium heat. Add ground beef, breaking up the meat with a wooden spoon. Cook until beef is no longer pink, about 6 minutes. Drain fat. Return to heat and add taco seasoning, then season with salt and pepper. Cook 1 minute more, then remove from heat.  Assemble pizzas: Place 3 tortillas on prepared baking sheet and spread 1/4 cup refried beans on each of them. Divide beef evenly between the tortillas, then top with 1/4 cup cheese each. Top with remaining 3 tortillas. Spread another 1/4 cup of refried beans on each tortilla, then top each with 1/4 cup cheese. Bake until cheese is melty and beans are warm, 10 to 12 minutes. Garnish with sour cream, tomatoes, olives, and green onions. Serve with hot sauce.