Mix chili powder, cumin, smoked paprika, garlic powder, onion powder, oregano, cayenne, salt, and pepper in a small bowl.
Heat olive oil in a large skillet over medium heat. Cook diced onion 2–3 minutes.
Add ground beef and cook until no longer pink, about 5–6 minutes. Drain fat.
Stir in garlic, cook 30 seconds. Add seasoning mix and water. Simmer 3–5 minutes until thickened.
Warm tortillas in a dry skillet or microwave wrapped in a damp towel.
Fill tortillas with beef and top with onion, cilantro, lettuce, and cheese. Serve with lime and salsa.