Mix all sauce ingredients together until combined. Cover and refrigerate for at least 30 minutes.
For the Onion Rings
Slice each onion into 1/2 inch thick rings. Carefully separate the rings.
In a medium-size bowl or zip bag, mix together the flour, garlic powder, paprika, salt & pepper.
In a separate bowl, whisk together the eggs and buttermilk.
Heat the oil to 350 degrees, either in a deep fryer or in a heavy pot.
Start by dipping the rings in the flour. Shake off the excess, and then dip the rings in the egg mixture. Return the rings to the flour mixture for final coating. Shake off the excess and place the rings in the oil. Do this process in batches. Avoid overcrowding the pan or fryer.
Fry the rings for about three minutes, turning halfway through, until golden brown. Remove from the oil with a slotted spoon onto paper bag or paper towel lined baking sheet.
Sprinkle with salt while still hot.
Cook time states 3 minutes. This is three minutes per batch of frying onion rings.