Steps
1. In a small bowl, mix olive oil, chili powder, garlic powder, salt, and pepper.
2. Rub the mixture all over the tuna steak, ensuring it's well coated.
3. Heat a skillet over medium-high heat and add the tuna steak. Cook for 2-3 minutes on each side for medium-rare, or until desired doneness.
4. While the tuna is cooking, prepare the avocado salsa by combining diced avocado, tomato, red onion, cilantro, and lime juice in a bowl.
5. Once the tuna is cooked, remove it from the skillet and let it rest for a minute.
6. Slice the tuna steak and serve it topped with the avocado salsa.