Step 1: Mix the Chicken - In a large bowl, add the ground chicken, salt, black pepper, paprika, cayenne pepper, garlic powder, onion powder, egg, and milk. Use clean hands or a spoon to gently mix everything together until evenly combined. Do not overmix. You want tender patties, not tough ones.
Step 2: Shape the Patties - Divide the chicken mixture into four equal portions. Shape each one into a thin patty that is slightly larger than your buns. They will shrink a bit as they cook, so give yourself some extra room.
Step 3: Make the Breading - In a shallow bowl, combine the all purpose flour, breadcrumbs or panko, and chili powder. Stir well so the spices are evenly distributed throughout the coating.
Step 4: Coat the Patties - Press each chicken patty into the breading mixture, coating both sides thoroughly. Gently press the coating into the surface so it sticks well. Set the breaded patties on a plate and let them rest for about five minutes. This helps the coating stay put when frying.
Step 5: Heat the Oil - Pour vegetable oil into a large skillet to a shallow depth and heat to 350 degrees Fahrenheit. The oil should shimmer and gently bubble when you drop in a small pinch of breading.
Step 6: Fry Until Golden - Carefully place the patties into the hot oil. Fry for three to four minutes per side until golden brown and cooked through. Do not overcrowd the pan. Work in batches if needed so the oil stays hot and the coating crisps properly.
Step 7: Drain and Rest - Transfer the cooked patties to a plate lined with paper towels. Let them rest for a minute so excess oil drains off and the coating stays crisp.
Step 8: Assemble the Sandwiches - Toast your hamburger buns if you like. Spread mayonnaise on the bottom bun, add the crispy chicken patty, top with shredded lettuce, and finish with the top bun. Serve hot and enjoy that first spicy crunchy bite.