Pour beer into the pancake mix container in place of the water it calls for. Make the batter as thick or thin as you prefer. Close the lid, give it a few shakes, and boom it's done.
Dip fish into the batter using a pair of tongs, or if you want to dirty a dish, pour the batter in a bowl first. If you cut your fish into smaller pieces, you can toss them into the container, close the lid and shake it a couple of times, then carefully remove the coated pieces.
Remove the fish from the batter using tongs, and place into the hot oil. Fry the fish until golden brown on both sides, 3 to 4 minutes per side.