2 skinless, boneless chicken breasts (about 6 ounces each)
Kosher salt and freshly ground pepper
1 teaspoon paprika
Peanut oil, for frying
1 large egg
1/2 cup nonfat milk
3/4 cup all-purpose flour
1/4 cup whole-wheat flour
1 tablespoon malted milk powder
1 tablespoon plus 1 teaspoon confectioners' sugar
1/4 teaspoon baking soda
1/4 teaspoon dry mustard
1 sour pickle, cut into 8 slices, plus 1 tablespoon pickle juice from the jar
2 teaspoons white vinegar
4 soft hamburger buns, split
1 tablespoon unsalted butter, softened