In a small bowl or a jar, whisk together the olive oil, lime juice, chili powder, cumin, paprika, garlic powder, onion powder, salt, black pepper, and cayenne pepper (if using).
Place your protein (chicken, beef, or shrimp) in a resealable bag or shallow dish. Pour the marinade over the protein, ensuring it is evenly coated.
Marinate in the refrigerator for at least 30 minutes, or up to 4 hours for best flavor. Discard any leftover marinade.
Notes
This marinade is incredibly versatile. Adjust the spices to your preference. For a spicier marinade, add more cayenne pepper.