Slice boneless, skinless chicken breasts horizontally into ½ inch thick fillets.

In a shallow bowl, combine all-purpose flour, salt, black pepper, garlic powder, onion powder, paprika, and cayenne pepper.

Whisk a large egg with a splash of water until smooth for the egg wash.

Place breadcrumbs in a third bowl for dredging.

Coat each chicken fillet in the flour mixture, dip it into the egg wash, then press into the breadcrumbs to fully cover.

Heat about ¼ inch of vegetable oil in a skillet over medium-high heat.

Fry each side of the chicken fillets for about 4-5 minutes or until golden brown and crispy.

While the chicken is frying, lightly toast your hamburger buns until golden brown.

Mix together mayonnaise, Dijon mustard, lemon juice, and lemon zest in a small bowl for the sauce.

Spread a layer of lemon mustard sauce on the toasted buns, layer with crispy chicken, followed by shredded lettuce, tomato, and parsley.

Serve immediately to enjoy the crunch and tenderness.