Heat olive oil in a large skillet over medium-high heat.
Add the chopped onion and cook for 3-4 minutes until softened.
Add the minced garlic and cook for 30 seconds until fragrant.
Add the ground beef to the skillet. Cook, breaking it apart with a spatula, until browned and cooked through, about 6-8 minutes.
Drain excess fat from the skillet if necessary.
Stir in chili powder, ground cumin, smoked paprika, dried oregano, cayenne pepper, salt, and black pepper. Mix well to coat the beef evenly with spices.
Pour in the tomato sauce and stir to combine. Reduce heat to medium-low and simmer for 5 minutes to let flavors meld.
While the beef simmers, warm the flour tortillas in a dry skillet or microwave until soft and pliable.
To assemble tacos, spoon the seasoned ground beef onto each tortilla.
Top each taco with shredded cheddar cheese, shredded lettuce, diced tomato, and chopped cilantro.
Add a dollop of sour cream on top and serve with lime wedges on the side for squeezing over the tacos.