Celery Root and Potato Soup with Chestnut Foam and Parsley Croutons

This recipe continues those served at last weekend's Community Green dinner. I meant to get them up sooner, but with Mom (and our beloved family dog Chloe) here recovering from surgery (just Mom, not our Dear Chloe), I haven't had a minute to breathe, let alone write! Now that she's doing great and I've packed her off to her own home, I can get back to business.

This is a grand special occasion soup, although none of the components take very long to prepare. You can make the stock and soup in advance, and prepare the chestnut foam up to the point where it comes out of the blender. Then just finish your foam, reheat the soup, and make the croutons. It would make a lovely first course for Thanksgiving, and is the perfect cool-weather weekend supper with some good bread, a salad, and a fresh fruit dessert.

You will need a whip with CO2 chargers to make the foam. If you don't have one, you can skip the foam and it will be simpler but still quite yummy, but if you are up to the investment, it's a great little product that will also make all kinds of cool dessert items.

Serves six to eight as a first course, or four heartier portions .
For Light Vegetable Stock:
8 cups water
3 carrots, peeled and roughly chopped
2 ribs celery, sliced
3 shallots, halved, skin left on
Peels from 4 Yukon Gold potatoes
1 bouquet garni: 1 bay leaf, 3 or 4 sprigs of fresh thyme, 8 black peppercorns, 1 small bunch fresh flat-leaf parsley

For Soup:
¼ cup olive oil
2 cups sliced leeks, white and light green parts only
2 cloves garlic, finely minced
1 large celery root (celeriac), peeled and diced
4 Yukon Gold potatoes, peeled and diced
8 cups light vegetable stock 1 bay leaf
1 teaspoon fine sea salt, divided
1 cup unsweetened almond milk
½ cup dry white wine
Freshly ground black pepper
Fresh lemon juice, to taste
Cayenne pepper hot sauce, to taste

For Chestnut Foam:
1 cup peeled, roasted chestnuts
1 cup light vegetable stock
¼ teaspoon fine sea salt
Freshly ground pepper
A pinch of cayenne pepper
½ teaspoon agar agar

For Parsley Croutons:
2 cups crusty French bread, cut into ½” cubes
¼ cup olive oil
2 tablespoons Earth Balance spread, melted
½ cup finely chopped flat-leaf parsley
Sea salt and freshly ground pepper


Prepare vegetable stock: Add all ingredients to a medium sauce pan. Simmer for about 45 minutes. Meanwhile, prepare soup and foam ingredients and Parsley Croutons.

Prepare Chestnut Foam:
Roast, peel and chop chestnuts (make an “x” in the bottom of each chestnut with a sharp knife. Roast at 400 degrees for about 35 minutes, or until peels begin to come away. Bottled unsweetened chestnuts may be substituted if necessary.) Combine chestnuts and 1 cup vegetable stock. Simmer for 25 minutes. Puree mixture in a blender on high setting. Strain with a fine mesh strainer, and return to sauce pan. Season with salt, pepper and a pinch of cayenne. Heat to a boil, add agar agar, and whisk to combine thoroughly. Chill mixture completely. Set aside in refrigerator. When ready to serve soup, add to a whip fitted with a CO2 charger to make foam.

Prepare soup:
Heat olive oil in a large sauce pan over medium heat; add leeks and a pinch of sea salt. Cook leeks for about 8 minutes, stirring frequently. Add garlic; sauté 1 minute more. Add celery root, potatoes, vegetable stock and remaining salt. Simmer for 25 minutes, or until ingredients are soft. Run soup through a food mill into a large bowl. Wipe sauce pan clean and return to the pot. Add almond milk, white wine and a liberal grinding of fresh pepper. Simmer for five minutes. Taste, and adjust acidity and flavor with fresh lemon juice and hot sauce. Keep warm until ready to serve.

Prepare Parsley Croutons:
Combine all ingredients. Spread on a heavy sheet pan and bake at 400 degrees, stirring frequently, until golden and crispy. Keep warm.

To serve soup:

Plate each individual portion. Top with chestnut foam and parsley croutons. Serve immediately.