Mix chili powder, cumin, salt, pepper, paprika, garlic powder, onion powder, red pepper flakes, and oregano together in a small bowl until combined.
1 tablespoon chili powder, 1.5 teaspoons ground cumin, 1 teaspoon sea salt, 1 teaspoon ground black pepper, 0.5 teaspoon ground paprika, 0.25 teaspoon garlic powder, 0.25 teaspoon onion powder, 0.25 teaspoon crushed red pepper flakes, 0.25 teaspoon dried oregano