This versatile dough is used to make the Flatbread with Asparagus, Fontina, and Pickled Onions, as well as the Goat Cheese and Greens Piadine. You can also make it ahead of time: Halve the kneaded dough, place each half in a zip-top plastic bag, and freeze for up to one month. Be sure to let the dough thaw in the refrigerator overnight or on the counter for 1 1/2 hours before shaping.
Lightly spoon flour into dry measuring cups; level with a knife.
Dissolve sugar and yeast in 6 tablespoons warm water in a large bowl; stir in 1/4 cup flour. Let stand 30 minutes or until bubbly. Add 1 3/4 cups flour, 1/2 cup warm water, and salt to yeast mixture; stir until a soft dough forms. Turn dough out onto a lightly floured surface. Knead until smooth and elastic (about 8 minutes); add enough of the remaining flour, 1 tablespoon at a time, to prevent dough from sticking to hands. Place dough in a large bowl coated with cooking spray, turning to coat top. Cover and let rise in a warm place (85°), free from drafts, 1 hour or until doubled in size. (Gently press two fingers into dough. If indentation remains, dough has risen enough.) Punch dough down; cover and let rest 5 minutes.