Stouts are complicated.
I’m not talking about the seemingly endless (and equally pointless) debate over the differences between stout and porter. I’m also not talking about the myriad combinations of baking-aisle adjuncts that can be added to a recipe. No, I’m talking about stouts themselves: Even with just grain, water, yeast, and hops, they are complicated flavor machines that push beer to its limits.
First, consider the many varieties of stout, and how they run the gamut from low to ultra-high ABV, sweet to acridly dry, light on the palate to thick and chewy, and malt bombs to hop-forward American varieties.