Coarsely chop the onion using the bamix® SliceSy® and the chopping blade. Melt the butter and sauté the onion in it. Add the pumpkin and steam. Then dust with flour, stir and add the vegetable broth and cream. Cook everything until the pumpkin is soft enough to pass through a sieve. Then purée with the bamix® multi-purpose blade. Stir in the spices and the crème fraîche. Whip briefly with the bamix® beater before serving. When serving, drizzle a little pumpkin seed oil on top or sprinkle with pumpkin seeds, depending on your taste.