01 - Combine chili powder, cumin, smoked paprika, garlic powder, onion powder, dried oregano, cayenne pepper, kosher salt, and black pepper in a small bowl. Mix thoroughly and set aside.
02 - Heat a large skillet over medium-high heat. Add ground beef, breaking it apart with a wooden spoon. Cook until browned throughout, approximately 5 to 6 minutes. Drain excess fat if necessary.
03 - Sprinkle the prepared seasoning mixture evenly over the browned beef. Stir well to coat the meat completely with spices.
04 - Pour in water and add tomato paste. Reduce heat to medium and simmer for 4 to 5 minutes, stirring frequently. Cook until the sauce thickens and coats the beef. Taste and adjust seasoning as needed.
05 - Heat tortillas in a dry skillet over medium heat for 30 seconds per side, microwave between damp paper towels for 20 seconds, or warm directly over an open flame until pliable and lightly charred.
06 - Spoon the seasoned beef mixture into each warmed tortilla. Top with shredded lettuce, diced tomatoes, cheese, red onion, cilantro, avocado, sour cream, and salsa as desired.
07 - Arrange tacos on a serving platter and serve while hot. Offer additional toppings on the side for guests to customize.