6tablespoonsmile-flavored lager beerat room temperature 1 tablespoon white vinegar
Whisk flour, salt and yeast together in a large bowl. Add water, beer, and vinegar. Mix until a shaggy ball forms. Cover bowl with plastic wrap and let sit at room temperature 8 to 18 hours.
Lay a 18 x 12 piece of parchment paper inside a 10 inch skillet and spray with vegetable oil. Transfer to a lightly floured counter and knead by hand 10 to 15 times. Shape dough into a ball. Transfer seam side down to the prepared skillet and spray the surface of the dough with oil spray. Cover loosely with plastic wrap and let rise until doubled in size, about 2 hours. (Dough should barely spring back when poked with knuckle.)
Thirty minutes before baking, adjust oven rack to the lowest position and place the Dutch oven (with lid) on the rack, and heat oven to 500 degrees. Lightly flour the top of the dough and, using a sharp or serrated knife, make one 6 inch long, 1/2 inch deep slash along the top of dough. Carefully remove the pot from the oven and remove lid. Pick up loaf by lifting parchment overhang and lower into pot (let any excess parchment hang over pot edge). Cover pot and place in oven. Reduce oven temperature to 425 degrees. Bake covered for 30 minutes. Remove lid and continue baking until crust is deep golden brown, 20 to 30 minutes longer. Carefully remove loaf from the pot and transfer to a wire rack. Discard parchment paper and let cool to room temperature, about 2 hours before slicing.
Store in plastic bag. Recrisp in the oven 6 to 8 minutes at 450-degrees.