To start, bloom your yeast. Mix your active dry yeast, sugar, and warm milk together and let sit for 10 minutes until foamy on top.
3/4 cup (180 ml) whole milk, 2 1/4 tsp active dry yeast, 1 tsp sugar
Next, in a large bowl of a stand mixer with a whisk attachment, mix flour, pumpkin pie spice, sugar and salt together.
4 3/4 cups (593 g) all-purpose flour, spooned and leveled, 2 tbsp granulated white sugar, 1 1/2 tsp salt, 1 1/2 tbsp pumpkin pie spice
To the dry ingredients add the whisked eggs, softened butter, pumpkin puree, and vanilla and mix.
2 eggs, whisked, 1/2 cup (112 g) unsalted butter, softened, 1 tbsp vanilla, 1/2 cup (122 g) canned pumpkin puree
Add in the yeast mixture and mix until everything is blended. Switch to a dough hook and knead on medium speed for 7-10 minutes until the dough pulls away from the edges of the bowl, forms a ball and springs back when pressed.
Form the dough into a ball. Place the dough in a large, greased bowl. Cover with plastic wrap or a kitchen towel and place in a warm place to rise, (outside or a cold oven with the light on works well for this), for 1- 1 ½ hours, or until the dough doubles in size.