Pat the fish fillets dry with paper towels.
In a bowl, combine flour, baking powder, salt, and pepper.
Add beer to the dry ingredients and whisk until smooth.
Heat oil in a deep pan over medium heat.
Dredge the fish fillets in flour, shaking off excess.
Dip the fillets into the batter, coating evenly.
Carefully place the battered fish in the hot oil.
Fry each side for about 4-5 minutes until golden brown.
Remove from oil and drain on paper towels.
Serve hot with lemon wedges and tartar sauce.