Soak chicken breast halves in pickle juice overnight.
Preheat oil in pressure cooker over medium heat to about 400 degrees F.
Take chicken out of pickle juice and pat dry.
In small bowl, beat egg and stir in milk.
In separate bowl, combine flour, powdered sugar, pepper and salt.
Dip each piece of chicken in milk until it is fully moistened. Roll moistened chicken in flour mixture until completely coated.
Drop chicken pieces into hot oil and close pressure cooker. When steam starts shooting through the pressure release, set timer for 3 1/2 minutes.
While chicken is cooking, spread a coating of melted butter on face of each bun.
When chicken is done, remove from oil and drain on paper towels.
Place two pickles on each bottom bun; add a chicken breast, then the top bun.
**NOTE: The chicken can be pan fried if a pressure cooker is not handy.