Stir the chicken pieces with the buttermilk and salt and refrigerate for 1 to 3 hours.
Whisk the rice flour, cornstarch, baking powder, garlic powder, paprika and pepper in a large bowl.
Drain the chicken for 30 seconds, toss it through the dry mixture and squeeze the coating onto each piece.
Spread the bites on a rack for 10 minutes while heating the oil to 350°F.
Fry in three small batches for 5 to 6 minutes, stirring once to separate the pieces and keeping the oil above 335°F.
Check a large bite for 165°F, then drain the batch on a rack and return the oil to 350°F before continuing.
Rest the finished bites for 4 minutes before serving.