Heat the oil over medium heat in a pot. If you have a thermometer, heat it until it’s between 325-350 degrees.
Cut the fish into thick strips (like you would see in a fish taco).
In a bowl, combine the dry ingredients.
In a separate bowl, whisk together the eggs and beer with a fork (careful–it can overflow). Quickly pour the liquid into the dry ingredients and stir. It’s ok if there are some clumps.
Sprinkle the fish with a bit more tapioca flour, dip in batter and place into oil.
Repeat and let fry for about 5 minutes, until golden brown.