Place a rack in the center of your oven and preheat to 400°F. Line a large rimmed baking sheet with parchment paper.
In a large ziptop bag or a bowl, place the chicken pieces. Add the flour and coat the chicken as evenly as possible, either by sealing the bag and shaking, or stirring with a large spoon.
In a medium, shallow bowl (a pie dish works well), beat the egg and milk. In a second shallow bowl, stir together the Panko, cornmeal, paprika, garlic powder, onion powder, and salt.
Bread the chicken: Working in batches, dredge the floured chicken in the egg mixture, then the Panko mixture, shaking off the excess flour and egg as you go and lightly pressing the Panko mixture as needed so the crumbs adhere. Arrange the breaded chicken pieces in a single layer on the prepared baking sheet.
Mist the tops of the chicken with nonstick spray. Bake for 9 minutes, then remove from the oven and flip the pieces over. Mist the tops with spray, then return to the oven and continue baking until the chicken is cooked through, about 6 to 7 minutes more—the pieces should no longer look pink in the center when cut in half. Immediately sprinkle with a small pinch of additional salt. Enjoy with your favorite nugget dipping sauces.
Notes
TO STORE: Transfer the cooked chicken nuggets to an airtight container and refrigerate for up to 4 days.
TO REHEAT: Reheat at 350°F in the oven or air fryer to restore the nuggets' crispy exterior.
TO FREEZE: Place the nuggets in a single layer on a parchment-lined baking sheet and freeze until solid. Once frozen, transfer them to a freezer-safe bag or container and freeze for up to 3 months. You can reheat the chicken nuggets directly from frozen.