Mushroom barley soup recipe - an earthy porcini mushroom broth brimming with leeks, barley and mushrooms perfectly balanced by a heavy pouring of tangy cashew sour cream at the very end. Dairy-free, vegan and good for you whole food!
Soak the cashews in hot water for 20 minutes then drain (If using a powerful blender such as a Vitamix there is no need to soak).
1/2 cup raw cashew pieces
Add the cashews, water and lemon juice to the blender and process until silky smooth. Refrigerate until needed.
1/2 cup raw cashew pieces, 1 lemon, 3/4 cup water
The Soup
Clean the Leeks - Slice the leek in half lengthwise then chop it up into small pieces. Place in a bowl and cover with cold water. Agitate the water to loosen up any dirt trapped between the layers then allow to sit undisturbed for 10 minutes or so for all the sand and dirt to sink yo the bottom.
1 medium leek
Preheat a heavy bottom soup over medium heat. Using a spider ladle or just your hands scoop the leeks out of the water and transfer them to the soup pot. No need to dry them as the pot is dry at this point. Add a pinch of salt and chili flakes and sautee the leeks until wilted. (Optional: Once all of the moisture has evaporated you can add a light drizzle of olive oil to get some caramelization going).
1 pinch red pepper flakes, sea salt + black pepper
Stir in the celery and mushrooms and toss to coat well. Sautee for a few more minutes until the mushrooms have released all their water and it starts to evaporate.
1 celery rib, 1 lb brown button mushrooms
Stir in the tomato paste, spices, thyme and tamari and simmer another minute or so then add the barley.
The Stock - Combine the porcini mushroom powder and the water to create the stock.
2 tsp porcini powder, 6 cups water
Pour the mushroom stock in the pot over the barley and bring to a constant simmer. Cover with a lid and cook for 45 minutes to one hour until the barley is cooked through. (If using pearled barley instead of hulled then it will be done in 20 minutes or so).
Pour in half of the cashew sour cream, taste and add more to your liking. Serve hot with extra red pepper flakes, chives, parsley or dill.
Notes
Porcini Mushroom Broth - This is where that deep earthy umami flavor comes from, it's an instant broth I made by mixing dried porcini powder with water. Alternatively you could go for about 1/4 cup of dried porcini mushrooms steeped in hot water for 20 minutes or so then into the soup pot it goes. This is different than any boxed mushroom stock one could grab from a supermarket shelf, it's truly worth the effort to make your own.
What can I sub for barley? - A good substitute for barley would be Farro, it has a similar texture but milder flavor. For a gluten-free option you can always use a short grain brown rice.