In a large bowl, combine pickle juice, cubed chicken, and ¾ c. milk. Marinate for 30-60 minutes.
In a large dutch oven, begin by heating 2 inches of canola oil over med/med-high heat until it reaches 360 degrees. Allow the heat to come back up between batches of chicken.
Cut the chicken breasts into 1.5 - 2 inch cubes, keeping them as evenly sized as possible, so they finish cooking at the same time.
Combine remaining milk and egg in a bowl. Drain marinated chicken and place in this bowl.
In a gallon-sized bag or another bowl, mix flour, confectioners sugar, and season with salt and pepper. Remove the chicken from the milk mixture, allow excess to drip off, and coat well with flour.
Cook chicken in oil without overcrowding the pan for 5-6 minutes, until deeply golden brown. Allow to drain on a cooling rack or paper towel. You can keep them warm in a 200°F oven while you finish cooking the rest if you would like!