In a medium mixing bowl, combine the ground turkey, garlic powder, onion powder, sea salt, black pepper, and 1 tablespoon of the buffalo sauce.
Gently mix with your hands until just combined, then form the mixture into one large, thick patty, pressing a small thumbprint into the center to prevent bulging.
Heat the avocado oil in a cast-iron skillet over medium-high heat until it begins to shimmer.
Place the turkey patty in the skillet and sear for 5-6 minutes without moving it to develop a deep, crispy golden-brown crust.
Flip the patty and cook for another 5 minutes, then sprinkle the blue cheese crumbles on top and cover the pan for 1 minute to allow the cheese to soften.
Remove the patty from the skillet and let it rest on a clean plate for 2-3 minutes to lock in the juices.
Lay out the butter lettuce leaves and place the burger in the center, drizzling with the remaining tablespoon of buffalo sauce and topping with sliced red onion.
Serve immediately with the sliced cucumbers on the side for a cool, hydrating balance to the spicy buffalo heat.