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Purple Sweet Potato Soup With Salted Mushrooms

This vibrant purple sweet potato soup is a stunning vegan dish that brings a sophisticated touch to your midweek lunch or dinner. The deep violet hue of the sweet potatoes creates a visually striking base, while the addition of coconut milk and warming spices like cinnamon and cumin provides a rich, velvety texture. Using purple potatoes adds an earthy sweetness that pairs beautifully with the tangy, salted mushrooms, which are roasted in balsamic vinegar to provide a delicious savoury contrast.

As a heart-healthy and gluten-free option, this homemade soup is ideal for those seeking a nutritious yet comforting meal. The recipe is simple to prepare, as the oven does most of the heavy lifting by caramelising the vegetables to enhance their natural flavour. Serve this soup hot with a drizzle of extra virgin olive oil and a scatter of fresh thyme for a professional finish that is sure to impress.

Continue reading below

Ingredients for Purple Sweet Potato Soup With Salted Mushrooms

  • 950ml chopped button mushrooms

  • 60ml balsamic vinegar

  • 4 tablespoons olive oil

  • Sea salt

  • 450g purple sweet potatoes (about 4 medium)

  • 1/2 sweet onion, chopped

  • 1/2 teaspoons ground cinnamon

  • 1/2 teaspoons ground cumin

  • 1/4 teaspoons chilli powder

  • Freshly ground black pepper

  • 475ml light coconut milk

  • 2 cups filtered water

  • 1/4 cup fresh thyme leaves, reserve 1 tablespoon total for garnishing all servings

  • Juice of 1 lemon

  • 1 tablespoon pure maple syrup

  • Olive oil, to garnish

  • Seek out purple sweet potatoes at your local natural foods store or Asian market, or use regular sweet potatoes.

Preheat the oven to 400ºF. Line two baking sheets with foil. In a large bowl, combine the mushrooms, vinegar, 2 tablespoons of the oil, and 1 tablespoon salt and stir to combine. Spread the mixture evenly on one of the lined baking sheets. Arrange the sweet potatoes on the second baking sheet. Place the mushrooms on the bottom rack and the sweet potatoes on the rack above. Bake the mushrooms for 30 minutes, until firm and dry, not crisp. Bake the sweet potatoes for 45 minutes, or until the natural sugars start to caramelize and they are soft when poked with a knife in the centre.

In a medium skillet, warm the remaining 2 tablespoons oil over medium heat. Add the onion, 1 teaspoon salt, the cinnamon, cumin, chilli powder, and pepper to taste and sauté for 5 minutes, or until the onion is fragrant and translucent.

Transfer the onion and baked sweet potatoes to a high-speed blender and add the coconut milk, water, the 60ml thyme, the lemon juice, maple syrup, and salt and pepper to taste. Blend until the soup is thick and creamy. Be sure to have the blender lid on securely before blending. (Alternatively, add the remaining ingredients to a soup pot and blend with an immersion blender.) If you find that it’s too thick (not all potatoes will have the same starch content), thin the soup with water. Adjust seasonings to taste.

Serve the soup in bowls, topped with 2 to 3 tablespoons of the mushrooms, a sprinkling of thyme, and a drizzle of olive oil. Serve hot/warm. Store in an airtight glass container in the refrigerator for up to 1 week.

Disclaimer

While every effort has been made to ensure the information is accurate and up to date, individual needs may vary and dietary requirements can differ based on personal health conditions. Always check food labels and allergen information before preparing or consuming any recipe. If you have specific health concerns, allergies, intolerances, or are following a medically prescribed diet, seek advice from your GP, pharmacist, or a registered dietitian before making significant changes to your diet or lifestyle.

Article history

The information on this page is peer reviewed by qualified clinicians.

  • 28 Jan 2026 | Originally published

    Authored by:

    UK recipe editors

    Peer reviewed by

    UK recipe editors
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