In a large mixing bowl combine water, yeast, and granulated sugar. Stir to combine, and allow to sit for about 5 minutes or until the yeast becomes nice and foamy.
Add pumpkin puree, egg yolks, salt, maple syrup, olive oil, pumpkin pie spice and 7 cups of bread flour to yeast mixture. Using a dough whisk or wooden spoon, mix to combine all ingredients.
Add in additional flour 1/2 cup at a time until the dough is no longer sticky.
Turn dough out onto a floured surface. Knead dough until smooth and elastic, about 6-8 minutes. (See note.)
Place dough into a greased mixing bowl. Cover; let rise until double in size, about 30 minutes.
Once dough has risen, punch down dough and turn out onto a floured surface.
Shape the loaf: Cut the dough in to 4 equal pieces. Pick one piece to start with, cover remaining pieces. Divide that piece into 6 equal pieces. Roll each of the 6 pieces into a "snake", about ½- to 1-inch thick.
Weave the long strips together (3 horizontal, 3 vertical), and then braid the four corners, tucking the ends in creating a round braided loaf.
Repeat the shaping process with the remaining 3 dough pieces.
Place each loaf in a greased baking dish (or glass pie dish); cover with plastic wrap and let rise until double in size.
Preheat oven to 350°F.
Once the bread has finished rising, brush each loaf with one egg yolk and then sprinkle with sesame seeds (optional).
Bake for about 40 minutes or until they are golden brown.
Enjoy warm, and share the baked goodness with someone you love!