1. Combine water and yeast in a bowl; let stand until foamy, about 5 minutes. Add flour, salt, sugar, and butter, stirring until a ragged dough forms. Transfer to a lightly floured work surface and knead with floured hands until elastic and tacky but no longer sticky, about 5 minutes. Transfer to a medium bowl brushed with oil, turning dough to evenly coat. Cover with plastic wrap and let stand in a warm, draft-free place until doubled in volume, 1 1/2 to 2 1/2 hours; or refrigerate until doubled in volume, at least 12 hours and up to 3 days (return to room temperature before using, 1 to 2 hours).