Ingredients
2 tablespoons olive oil
1 medium onion, chopped
Coarse salt and freshly ground pepper
6 cups peeled, chopped celery root (from about 2 large celery roots)
1 cup peeled and chopped Yukon gold potatoes (from about 1 potato)
10 cups homemade or low-sodium store-bought vegetable stock
2 cups peeled, cored, and quartered ginger gold apples (from about 2 apples), plus 1 apple, cored and sliced into thin wedges, for garnish
1/4 cup celery leaves or leaves from celery root stem, for garnish
Preparation
In a large heavy-bottomed saucepan, heat olive oil over medium heat. Add onion and season with salt; cook, stirring until onions are soft and translucent, 5 to 7 minutes. Add celery root, potato, and vegetable stock; reduce heat to medium-low and simmer until potatoes are soft, 15 to 20 minutes.
Add apples and continue simmering for 5 minutes. Remove saucepan from heat and puree using an immersion blender or, working in batches, using a conventional blender; season with salt and pepper. Serve immediately garnished with apple slices and celery leaves.