Beer-battered fish, or for that matter any fried fish, needs to be two things: Crispy on the outside, tender on the inside. I am an official porter convert for beer battered fish—it has a weight and flavor depth that ales can't provide. A little panko in the mix and you're bound to have just the right amount of crisp on the outside. —Samantha Weiss Hills
Fill a dutch oven with vegetable oil, so that oil comes up a little less than halfway up the pot. Place over low heat and heat to 375F. Meanwhile, prepare your beer batter by combining the beer, 1 cup of flour, and a teaspoon of salt in a large bowl. Set aside. Place remainder of flour (and optional panko) in a resealable bag and set aside with the beer batter.
Divide fish into 1/2- or 1/4-pound servings. Place fish filets in the bag of flour to lightly coat, then dip into beer batter, and add to the oil. Fry until golden brown, turning fish occasionally, about 8 minutes, depending on the size of the filets. Remove from oil and drain on paper towel-lined plate for a minute before plating. Serve fried fish wedges of lemon for garnish, and tartar sauce and malt vinegar on the side.