Purple yam soup with ginger and garlic, fresh dill, bean sprouts and walnuts

The purple yam gives this very simple soup a vibrant dark purple colour; the walnuts and bean sprouts, a rich texture.

1T cooking oil
1/4t coarse sea salt
1T fresh garlic, minced
1t fresh ginger, minced
1/4 cup fresh dill fronds and 2T minced
2 cups purple yam, peeled and diced (1/2″)
4 cups vegetable stock
2T nutritional yeast, divided
1T tapioca flour dissolved in 2T cold water
1/2 cup mung bean sprouts
1/4 cup chopped walnuts
Sea salt and black pepper to taste

In a larger pan with a lid, bring the cooking oil to heat on medium high.
Add the sea salt, garlic, and 2T dill; saute for 2 minutes.
Add the yam and saute another 2 minutes.
Add the stock and deglaze the pan.
Cover, reduce heat to low, and simmer until the yam is fork tender.
Remove from heat, add 1T nutritional yeast, and puree the soup.
Return the pan to a light simmer.
Add the tapioca solution slowly stirring continuously until it thickens.
Season to taste.
Ladle out the soup and garnish with bean sprouts, dill fronds, walnuts and nutritional yeast.