01 - Combine chili powder, ground cumin, smoked paprika, garlic powder, onion powder, dried oregano, cayenne pepper (if using), salt, and black pepper in a small bowl. Set aside for later use.
02 - Heat a large skillet over medium-high heat. Add the ground beef and cook, breaking it apart with a spoon, until fully browned and cooked through (approximately 5-6 minutes). Drain any excess fat.
03 - Add the finely chopped onion and minced garlic to the skillet with the cooked beef. Sauté for 2-3 minutes until the onion softens and becomes fragrant.
04 - Sprinkle the prepared homemade taco seasoning over the beef mixture. Stir in the tomato paste and water, ensuring all ingredients are thoroughly combined.
05 - Reduce the heat to medium-low. Allow the mixture to simmer for 5-7 minutes, or until it thickens and most of the liquid has been absorbed.
06 - While the beef filling simmers, warm the tortillas. This can be done in a dry skillet over medium heat for about 30 seconds per side, or by wrapping them in foil and heating them in a low oven.
07 - To assemble, spoon a portion of the beef mixture into each warm tortilla. Top with shredded lettuce, diced tomatoes, shredded cheese, sour cream, chopped cilantro, and a squeeze of fresh lime juice.
08 - Serve the assembled beef tacos immediately.