n a large nonstick skillet over medium heat, cook the ground beef or turkey with the salt and pepper, breaking the meat into small pieces, until cooked through, 5 to 8 minutes. Drain any excess grease.
Stir in the chili powder, cumin, and tomato sauce. Bring to a simmer and cook for 3 to 5 minutes.
Preheat the oven to 375°F and lightly grease two muffin tins.
Cut 4-inch circles from the tortillas using a cookie cutter or a round lid. Gently press each circle into a muffin well to form a cup.
Scoop a spoonful of the meat and sauce into each tortilla cup, then top with a sprinkle of cheese.
Bake for 10 to 12 minutes, until the tortillas are lightly golden around the edges and the filling is hot and bubbly.
Carefully remove the cups from the muffin tin and serve warm with your favorite taco toppings.