Place the pan on the Q grill and preheat for 10 minutes.
Add the oil, onion, and garlic to the pan, close the lid, and cook until softened, 4 to 5 minutes, stirring occasionally. Add the cumin, paprika, and chili flakes and stir into the onion.
Add the beef mince to the pan, breaking it up with a spoon or spatula. Close the lid and cook until the beef is browned, 6 to 8 minutes.
Add the crushed tomatoes and season with salt and pepper. Close the lid and continue to cook until the sauce has thickened, 6 to 8 minutes, stirring occasionally.
In the last minute add the taco shells to the grill and heat for 30 seconds on each side.
Spoon the beef mixture into the taco shells and top with lettuce, chopped tomato, and cheese. For added flavors, you can also use avocado, sour cream, and salsa.
