Purple Sweet Potato and Purple Cauliflower Soup (Keto, Paleo)

I know it sounds wild but this smooth, sweet soup is so good! If you’ve ever tried cooking with purple sweet potatoes you know the disappointment that comes from watching that gorgeous dark flesh turn an unsavory shade of grey. Adding purple cauliflower takes that palid potential and turns it into a proper purple!

Wanna play with color? If you add a little bit of acid (like a tablespoon of lemon juice) you can transform the purple into a deep magenta!

Purple Potato and Purple Cauliflower Soup

  • 1 large purple cauliflower
  • 1 1/2 lbs purple sweet potatoes
  • 1 tbsp butter
  • 1 medium shallot, peeled and chopped
  • 1 leek
  • 1 1/2 inch ginger, peeled and grated
  • 4 cups veggie broth
  • 1 tsp Cinnamon
  • 1/2 tsp Nutmeg
  • 1 cup heavy cream OR full fat coconut milk (for Paleo)
  • 2 tbsp honey (exclude for Keto)
  • Optional: Candied nuts to garnish (exclude for Keto)


  • Peel the purple sweet potatoes and cut them into 2 inch chunks.
  • Core the purple cauliflower and cut it into chunks.
  • Wash the leek and cut the white part into narrow strips. Discard the green.
  • Peel then dice the shallot. Peel the ginger and grate it.
  • Melt the butter in the bottom of a dutch oven or soup pan. Add the leek and cook for 2-3 minutes. Add the shallot and cook for another 2-3 minutes. Add the ginger and continue cooking for yet another 2-3 minutes (total 6-9 minutes cooking time.)
  • Pour in the chicken broth. Scrape up any browned bits at the bottom of the pan.
  • Add the cinnamon and nutmeg. Mix well.
  • Add the chopped sweet potato and cauliflower.
  • Bring the mix to a boil. Put a lid on it and turn it down to simmer until the potatoes are soft.
  • Add the heavy cream (or Coconut Milk, for Paleo) and honey (exclude honey for Keto). Continue to simmer, uncovered, for another five minutes.
  • Remove from heat and let cool for 10 minutes. Process in a blender in batches until all of the soup is smooth.
  • Optional: Garnish with your favorite candied nuts. Pecans or pistachios work particularly well!

I spent a very busy day making this purple perfection for a client who needed soft foods in their life. In seven hours (including grocery shopping!) I made six soups from scratch, three entrees, and two desserts.

It was a heck of a juggling act since there were only 4 burners and three pots big enough for soup, but I am a master of multi-tasking!