01 - Preheat oven to 350°F.
02 - In a large skillet over medium heat, cook ground beef until browned, breaking it apart with a spoon, approximately 4 to 5 minutes. Drain excess fat if necessary.
03 - Add chopped onion and cook for 2 minutes until softened. Stir in minced garlic and cook for 30 seconds.
04 - Mix in tomato paste, chili powder, cumin, smoked paprika, oregano, cayenne pepper, salt, and black pepper. Cook for 1 minute until fragrant.
05 - Pour in beef broth or water and stir to combine. Simmer on low heat for 5 to 6 minutes until the mixture thickens. Remove from heat.
06 - Place hard taco shells on a baking sheet and warm in the oven for 3 to 4 minutes.
07 - Spoon beef mixture into each shell. Top with shredded cheese, lettuce, tomato, red onion, sour cream, and cilantro.
08 - Serve immediately with lime wedges on the side.