Here is a recipe I’ve been using for awhile now, I found it on a YouTube search. It’s pretty close as I remember it. I lived in Cali for a few years early 80’s, and have missed Pioneer Chicken ever since I left in 85.
1 chicken , cut into 8 pieces
1 cup cornstarch , 1/4 cup reserved for coating
1/4 cup flour
1 tablespoon paprika
1 1/2 tablespoon onion powder
1 3/4 teaspoon salt
3/4 teaspoon celery salt
1/2 teaspoon black pepper
1 teaspoon baking soda
1/2 teaspoon baking powder
3/4 cup water
3 cups peanut or canola oil
Mix all the dry ingredients except for the reserved 1/4 cup cornstarch.
Add the water and whisk.
Put 1/4 cup of cornstarch in shallow pan and coat chicken with it.
Dip the chicken that has been coated in cornstarch into the wet batter until completely coated.
Let drip for a couple of seconds and gently lower into pot of oil.
Fry in 350 degree peanut or canola oil. for 8-10 minutes until cooked through in small batches.
Drain on metal rack, not paper towels, that would make it soggy.