Combine dry ingredients in a bowl. Whisk in beer until a thick, lumpy batter forms.

Pour oil into the fryer, and heat to 365°F. Maintain temperature while frying.

Rinse fillets, and pat dry. Dip in the batter to evenly coat.

Carefully lower fillets, one at a time, into the hot oil. Fry several fillets at a time, turning once, until cooked through and golden brown, about 2 minutes per side.

Transfer fried fillets to paper towels. Allow oil to drain for 1-2 minutes.

Serve fish hot with desired sauces. Garnish with parsley if desired.