Step 1: Prepare the Chicken : Slice chicken breasts horizontally to create thinner cutlets. Pound lightly to even thickness for consistent cooking. Season both sides with salt and pepper.

Step 2: Set Up the Breading Station : Place flour in one shallow bowl. Beat eggs with water in a second bowl. Place panko breadcrumbs in a third bowl.

Step 3: Bread the Chicken : Dredge each chicken cutlet in flour, shaking off excess. Dip into the egg mixture. Coat generously in panko, pressing lightly to help the crumbs stick.

Step 4: Fry the Chicken Katsu : Heat oil in a deep skillet to 340–350°F (170–175°C). Fry chicken cutlets for 3–4 minutes per side until golden and cooked through. Transfer to a wire rack or paper towels to drain excess oil. Let rest for 2 minutes before slicing.

Step 5: Make the Tonkatsu Sauce : In a small bowl, mix ketchup, Worcestershire sauce, sugar, soy sauce, vinegar, and mustard. Stir until smooth and set aside.

Step 6: Slice and Serve : Slice Chicken Katsu into strips. Serve hot with Tonkatsu sauce drizzled over or on the side.