01 - Preheat oven to 375°F. Lightly grease a 12-cup muffin tin with cooking spray or oil.
02 - Cut tortillas into circles slightly larger than the muffin cups (about 4 inches diameter). Press each circle firmly into a muffin cup to form a shell. If using wonton wrappers, use one per cup.
03 - Bake the tortilla cups for 5-6 minutes until just starting to crisp. Remove from oven but keep in the tin.
04 - While cups bake, heat a skillet over medium heat. Add ground beef and cook, breaking it up with a spoon, until browned. Drain excess fat if needed.
05 - Add chopped onion and garlic to the beef. Cook for 2 minutes until softened. Stir in taco seasoning and tomato sauce. Simmer for 3 minutes until slightly thickened. Remove from heat.
06 - Spoon the beef mixture evenly into the tortilla cups. Top each with shredded cheese.
07 - Return to oven and bake for 7-8 minutes, or until cheese is melted and cups are golden.
08 - Cool for 2 minutes, then carefully remove taco cups from the tin.
09 - Top with a dollop of sour cream, diced tomatoes, cilantro, olives, and jalapeño as desired. Serve warm.