In the bowl of a food processor, pulse the bread flour, salt, and instant yeast together to combine. Add pumpkin purée, maple syrup, and melted butter , and process until the dough comes together in a smooth, pliable ball; the timing can vary depending on the size and power of a given food processor, but expect about 75 seconds from start to finish. To test the dough, tear off a small piece and stretch gently in all directions; when the dough is ready, it can be pulled into a thin, translucent sheet.
