To prepare a vegetarian pumpkin soup recipe, you will first need to prepare your pumpkin. Cut the pumpkin in half lengthwise and scoop out the seeds. Peel the skin off and cut the flesh into cubes. Place the cubed pumpkin flesh, skin, seeds, and seeds into crock pot and bring to boil. Reduce the heat to low and simmer for 1 to 2 hours or until pumpkin is tender. Remove from heat and let cool. Puree the soup until smooth. Serve with sour cream, if desired.