To prepare a butternut squash sweet potato ginger bisque recipe, you will first need to prepare the sweet potatoes. Peel and slice the Sweet Potatoes. Cut the Butternut Squash in half lengthwise and scoop out the seeds. Place the squash halves, skin-side down, in the crock-pot and cover with water. Bring the water to boil, then reduce the heat to medium-low and simmer until tender, about 30 minutes. Remove the pot from the stove and add the butter, sugar, and cinnamon. Simmer the mixture until the sugar is dissolved and the puree is thickened, 1 to 2 hours.