Sourdough starter  only has two ingredients: flour and water. But while water is self-explanatory, you have more options when it comes to your choice of flour. So what’s the best flour for sourdough starter? The simplest answer:  All-purpose flour  is a great choice to feed your sourdough starter. It’s what many bakers choose — it’s basic, easy, and often what you already have in your pantry. With that said, you can feed your sourdough starter with other types of flour, too — here are your options, and more details on each. Photography by Rick Holbrook; food styling by Kaitlin Wayne Our go-to flour for sourdough starter is all-purpose flour. Option 1: All-purpose flour You don’t need anything special for your starter — all-purpose flour works just fine, and it’s what most bakers use for their starter.…