Heat olive oil in a large skillet over medium-high heat.
Add ground beef and cook for 5–7 minutes, breaking it apart, until browned. Drain excess fat if needed.
Stir in chili powder, cumin, oregano, garlic powder, salt, and black pepper.
Add tomato paste and water. Stir well to combine.
Reduce heat to medium-low and simmer for 3–5 minutes until the mixture thickens and becomes saucy.
Warm tortillas and fill with seasoned ground beef.
Top with lettuce, tomatoes, cheese, and red onion. Serve immediately.