Mix the milk and pickle juice in a large ziplock bag. Whisk the egg slightly and add it to the marinade.
Then add the bite size chicken pieces to the marinade. Set this in the fridge for at least 2 hours. (overnight is fine)
Whisk the dry ingredients together in a large bowl: flour, powdered sugar, salt, pepper, garlic powder and cornstarch.
Set a wire rack next to the bowl of dry ingredients. Prepare a plate next to the stove, lined with paper towels, to set the fried chicken on.
When the chicken is done marinating, remove it from the marinade (I used tongs, or you could use a slotted spoon) and put it into the bowl with the flour mixture. Toss all of the chicken pieces well. When all of the pieces are coated, place the chicken pieces onto the wire rack and allow the chicken to rest while you heat the oil.
Heat the oil to medium (about 350 °F (177 °C)) in a deep skillet or dutch oven.
Fry about half of the chicken at a time, or even smaller batches, don’t crowd the chicken as you fry it. Fry the chicken nuggets until golden brown. (3-5 minutes until cooked through. I recommend testing a couple first)
Place the fried chicken on a paper towel lined plate. Then fry the rest of the chicken.