1. In a large skillet over medium-high heat, brown the ground beef while breaking it apart with a wooden spoon.

2. Once the beef is mostly cooked, drain excess fat if needed, then stir in the chopped onion and garlic. Cook for 2–3 minutes until soft and fragrant.

3. Add chili powder, cumin, paprika, oregano, salt, and pepper. Stir to combine and coat the meat evenly.

4. Stir in tomato paste or tomato sauce and water. Simmer for about 5 minutes until the mixture thickens.

5. Meanwhile, warm taco shells in the oven or a dry skillet until just crisp.

6. Fill each shell with the beef mixture, then top with lettuce, diced tomatoes, onion, and shredded cheese. Add optional toppings as desired.

7. Serve immediately while warm and crispy.