Sourdough Guinness Sourdough IngredientsIngredients for a loaf of beer-based sourdough.Slice of SourA slice of sourdough bread rests on a cutting board.Honey Brown Lager BreadA loaf of sourdough inside the oven.Honey Brown Lager BreadA loaf of sourdough cools on the countertop.Sour HeelThe heel of a loaf of sourdough bread rests on a cast iron pan.Proof of BreadA well-proofed loaf in a baneton.Sour-dudOver-proofed bread from late-June 2021 during a local heat wave.