Brown butter in a saucepan over medium-low heat. Once it's dark golden in color, add onions, garlic, and ginger to the pan. Let cook for 2-3 minutes.
Once onions are translucent, add spices and stir in well. Let this cook for 1-2 minutes, then add pumpkin and chicken broth into the pan. Stir in well.
Bring to boil, then turn to low and allow to simmer for 20 minutes. After 20 minutes, use immersion blender to puree everything smooth.
Let simmer for an additional 20 minutes. In the mean time, cook 4 slices of bacon.
Once the soup is done, add heavy cream and bacon grease and mix in well.
Crumble bacon over the top and optionally add chopped parsley and 2 tbsp. sour cream.