Into a large mixing bowl whisk together the buckwheat flour, brown rice flour, sorghum flour, potato starch, tapioca starch, oat flour, yeast, brown sugar, spices and salt.
In a medium bowl whisk together the water, milk, pumpkin puree, psyllium husk and flax seed, until completely combined.
Pour the psyllium mixture into the middle of the flour blend and stir with a spoon to create a shaggy dough.
Place the dough on a lightly floured work surface, knead and and shape the dough into a ball.
Place a large sheet of parchment paper on the work surface, and dust the paper generously with flour. With a rolling pin, roll out the dough to a rectangle that's roughly 12 inches by 9 inches.