Creamy Japanese Sweet Potato Potage (Vegan)
*Potage* is what Japanese home cooks call a smooth, blended vegetable soup, and sweet potato is the fall classic. Japanese sweet potatoes are dense, starchy and naturally sweet, so the soup needs very little help: an onion, water, and a spoonful of shiro dashi for a quiet savory backbone.
Instead of butter and cream, this version blends in a couple of tablespoons of ground hazelnuts or cashews and finishes with soy milk. The result is thick and velvety without any dairy, and it's on the table in about 20 minutes.
Ingredients
- Japanese sweet potatoes2 medium
- Onion1/2
- Hazelnuts or cashews2 Tbsp
- Soy milkunsweetenedscant 2/3 cup
- Water2 cups plus 2 Tbsp
- Shiro dashi (8x concentrate)check the label — see substitutions1 Tbsp
- Sea salt1 tsp
- Dried parsleyto taste
Nutrition
per serving🛒 Ingredient notes & substitutions
Shiro dashi: Most bottled shiro dashi contains bonito (fish), so check the label for a kombu- or shiitake-based vegan one. If you can't find it, season to taste with kombu dashi powder or vegetable bouillon plus a little light soy sauce.
Japanese sweet potatoes: Orange sweet potatoes work too; the soup will be a little less starchy and more orange than the photo.
Hazelnuts or cashews: The nuts stand in for butter and add creaminess. You can leave them out and the soup still works.
Instructions
Peel the sweet potatoes and the onion and slice both into thin rounds.
Put the sweet potatoes and onion in a pot, add the water, and simmer until completely tender.
Once the sweet potatoes are cooked through, stir in the shiro dashi to season.
Grind the nuts to a fine powder in a blender.
Blend the cooked sweet potatoes, then add the ground nuts and blend again until smooth.
Return the soup to the pot, add the soy milk, and warm it gently over low heat.
Taste and adjust with the sea salt.
Ladle into bowls and sprinkle with dried parsley.
Tips
The ground nuts are doing the job butter usually does in a potage — they add body and richness without any dairy. If you don't have any, simply skip them.
Don't let the soup cook hard once the soy milk is in. Overheating soy milk dulls the flavor, so just warm it through over low heat.