In a medium bowl, combine the ground chicken with kosher salt, garlic powder, and onion powder. Mix gently until just incorporated. Let the mixture rest for 5 minutes while you set up your breading station.

Lay a large sheet of parchment paper on a work surface and dust it generously with flour. Place the seasoned meat in the center.

Using your hands, press the meat into a very thin, large oval shape, about 1/4-inch thick, aiming to nearly cover the size of a standard sheet pan. Lightly sprinkle the top surface with more flour.

Brush the top of the meat with the egg wash, making sure to cover it evenly. Sprinkle a generous layer of panko breadcrumbs over the egg wash, pressing gently so they adhere.

Spray the breadcrumb layer thoroughly with avocado oil until the crumbs are fully saturated and glistening. This step is key for achieving a crispy, oven-fried texture.

Place another large sheet of parchment paper on top of the breaded cutlet. Carefully flip the entire assembly over so the unbreaded side faces up. Peel away the top parchment.

Brush the exposed side with the remaining egg wash, then coat it completely with panko, pressing gently. Spray this side generously with avocado oil until the crumbs are fully hydrated.

Lightly spray a large rimmed sheet pan with avocado oil. Gently transfer the breaded cutlet from the parchment to the prepared pan, smoothing out any wrinkles.

Bake in a preheated 450°F convection oven (or use the air fry setting if available) for 15 minutes, until the cutlet is cooked through and the breading is starting to brown.

Switch the oven to broil. Broil the cutlet for 4 to 5 minutes, watching closely, until the top is deeply golden and crispy. Rotate the pan halfway through if needed for even browning.

Remove the cutlet from the oven and immediately sprinkle with flaky sea salt. Let it rest on the pan for 1 to 2 minutes, then slice into portions and serve hot.