The elasticity of dough and the eventual possible toughness of the crust is determined by the amount of gluten, a kind of protein, in the flour. All-purpose flour has varying amounts of gluten depending on what part of the country you’re from; flour from the South typically has less gluten and is more suitable for baking pastry than Northern flour, which is considered “harder.” If you’re uncertain of your flour, try using equal parts all-purpose flour and cake flour, which contains virtually no gluten. Flour with a higher gluten content will also absorb more liquid.