Prepare lettuce and tuna.
Wash the lettuce thoroughly and cut it into bite-sized pieces.
Heat olive oil in a pan and sauté minced garlic.
Add tuna (drained) and stir-fry, then season with salt and pepper.
Place the lettuce in a bowl instead of rice, and add the sautéed tuna on top.
Top with cherry tomatoes or avocado and drizzle with dressing if desired.