Heat the oil in a medium skillet over medium-high heat. Add the ground beef and cook for 6 to 8 minutes, breaking up the meat into small pieces as it cooks. Drain and discard any excess grease if necessary.
Add the tomato paste, water, chili powder, ground cumin, salt, garlic powder, onion powder, and dried oregano. Stir together until fully combined. Cook for 1 more minute.
Remove the skillet from the heat and stir in the lime juice.
Serve ground beef in warm corn tortillas topped with shredded lettuce, cheese, tomatoes, and sour cream.
Notes
Beef: I like using 85% lean ground beef to keep the taco meat juicy and moist without it being overly greasy.
Tomato paste: You can use ½ cup of tomato sauce instead of the tomato paste and water.
Reheating: Add a splash of water or broth when reheating the taco meat to help prevent it from drying out.