Place the chicken between two sheets of plastic wrap and pound to an even ¼-inch thickness.
Season both sides of the chicken with the kosher salt and black pepper.
In a shallow bowl, whisk together the flour, seasoning salt, garlic powder, onion powder, paprika, and black pepper.
In a second shallow bowl, whisk together the eggs, water, salt, and black pepper.
In a third shallow bowl, combine the panko, Parmesan cheese, salt, garlic powder, onion powder, Italian seasoning, and lemon zest.
Dredge each piece of chicken in the flour mixture, shaking off any excess.
Dip into the egg mixture, allowing any excess to drip off.
Press firmly into the panko mixture, coating both sides evenly.
Place the breaded chicken on a wire rack and let rest for 5 to 10 minutes. This helps the coating adhere during cooking.
Pour about ¼ inch of avocado oil into a large skillet and heat over medium heat until the oil reaches 350°F.
Carefully add the chicken to the hot oil, working in batches if needed. Cook until golden brown and crisp:
Chicken thighs: 3 to 4 minutes per side, or until the thickest part reaches 175°F. Chicken breasts: 2 to 3 minutes per side, or until they reach 165°F.
Transfer to a clean wire rack and immediately sprinkle with flaky salt.
Serve warm with lemon wedges and an extra squeeze of fresh lemon juice, if desired.