Parmigiano-Reggiano cheese makes this super-crunchy chicken extra flavorful. Slideshow: More Best Chicken Recipes
Preheat the oven to 425°. Place one oven rack on the highest level and another in the middle of the oven. Line a baking sheet with parchment paper.
In a medium bowl, mix the Parmigiano-Reggiano and the panko. In a another medium bowl, mix the flour, sea salt and freshly ground pepper. In a separate medium bowl, whisk the egg with 1 teaspoon of water.
Rinse the chicken breasts under cold running water. Dip each piece of chicken in the flour so that it is well coated, then dip it in the egg and finally in the panko.
Place the chicken on the prepared baking sheet and drizzle melted butter over each piece.
Bake for 15 minutes in the middle of the oven. Turn on the broiler, move the chicken to the top rack and broil for 5 minutes, until the top is crispy and an instant-read thermometer reaches 165°.
Meanwhile, in a medium bowl, whisk together the mayonnaise, yogurt, Dijon mustard, sugar, apple cider vinegar, sea salt and freshly ground pepper. Add the cabbage and mix well. Divide the chicken breasts among 4 plates and serve with the coleslaw on the side.