Cut the chicken breasts into 2” (5cm) pieces.
Stir together 2 cups of cold water, 1½ tablespoons of the salt and Worcestershire until the salt dissolves. Add chicken to the brine then cover and refrigerate for 30 minutes to 1 hour.
In one mixing bowl combine the flour, panko bread crumbs, remaining salt, onion powder, black pepper, garlic powder and baking soda. Then, in another mixing bowl whisk the egg whites until foamy.
Remove chicken from the brine and pat dry with paper towels. Heat oil in a large cast iron pan or Dutch oven (it should be enough oil to reach 1” (2.5cm) up the side of the pot or pan). Heat oil to 350ºF (180ºC).
Working in batches, add chicken pieces to the egg whites, turning to coat. Then toss the chicken in the breadcrumb and flour mixture until evenly covered.
Shake off any excess breading, then fry in the oil, turning occasionally until golden brown all over, about 4 minutes total.
Add the ingredients for the sauce in a medium mixing bowl. Whisk to combine.
Remove the chicken to a cooling rack set over a baking sheet to drain. Repeat with the remaining chicken. Serve hot with the dipping sauce.