In a large bowl or stand mixer, whisk together warm water, yeast, pumpkin puree, maple syrup and salt.
1 ½ cups warm water, 2 ¼ teaspoons instant yeast, 1 cup pumpkin puree, 2 tablespoons maple syrup, 1 teaspoon kosher salt
In a separate bowl, whisk together flour, cinnamon, and pumpkin pie spice. Add dry mixture to the wet mixture. Stir until a shaggy, sticky dough forms. Cover and let rest 10 minutes.
4 ¾ cups all-purpose flour, 1 tablespoon ground cinnamon, 1 ½ teaspoons pumpkin pie spice
After the rest, knead dough with dough hook 2 to 3 minutes until smoother. This is a very wet, sticky dough, closer to a thick batter than a firm ball. Resist the urge to add extra flour. Use a stand mixer with a dough hook if possible. If mixing by hand, knead in a large bowl with a dough scraper.
Note: Pumpkin puree can vary in moisture. If your dough feels excessively loose, you may add a very light sprinkle of flour, but avoid adding too much. Extra flour will mute the pumpkin flavor and spices. The dough is meant to be sticky, so give it time to hydrate, and it will naturally thicken and strengthen.
Transfer dough to a lightly greased bowl using a spatula, cover, and let rise until doubled. This will take at least 1–1 ½ hours, possibly longer.