Pat the cod dry with a paper towel and set aside.
Whisk together the flour, baking powder, sugar, garlic powder, onion powder, paprika, salt, and pepper in a large bowl.
In a small bowl, whisk together the beer and egg.
Pour the wet ingredients into the dry and whisk together until there are no lumps.
Heat a deep fryer or dutch oven with 4 inches of oil to 375°F.
Dip a piece of cod into the batter and let any excess drip off.
Carefully place the cod into the hot oil. If using a deep fryer, immediately shake the basket, so it doesn’t stick on the bottom. Do not crowd the fryer, I fry 2 pieces of fish at a time.
Fry until golden brown, flipping a few times to cook evenly, about 8 minutes total or until an internal temperature reaches 145°F.
Place the pieces onto a paper-towel-lined plate to absorb any excess oil and immediately sprinkle with a little more salt.
Place the finished pieces on to a wire rack over a sheet tray while you fry the remaining cod.