Preheat the oven to 425°F and lightly grease a baking sheet or large cast-iron skillet.
Mix the flour, baking powder, sugar, and salt.
Cut the butter into pieces, and work into the flour mixture with your hands or a pastry blender until it resembles pea-sized crumbs.
Pour in the beer and stir until a shaggy dough forms.
Place the dough on a floured surface and knead for a minute. Now the dough should be smooth and no longer wet. (You can sprinkle more flour on the surface if you find that it’s sticking.) Roll out the dough until it’s 1/4 of an inch thick and then fold over in half.
Using a round cutter, cut the biscuits from the folded dough. (You may have to gather the scraps and roll again if you run out of room while cutting.) Place the cut biscuits on the greased baking sheet or skillet close together (so they rise and do not spread) and bake for 20-25 minutes or until the tops are golden brown.
Serve warm. They will keep covered for a day or so, but are best fresh out of the oven. They can also be frozen.