1 medium kabocha squash, peeled
1 medium celery root, peeled
2 tablespoons unsalted butter
1/4 cup water
Salt and freshly ground black pepper, to taste
Crème fraiche (optional)
Preheat oven to 350 degrees F.
Cut kabocha and celery root into 1/2-inch slices. Combine with butter, water, salt, and pepper in a medium saucepan. Cover and bake until tender, 15 to 20 minutes.
Finely grind vegetables in a food processor or meat grinder. Adjust seasonings and stir in a touch of crème fraiche if desired. Serve hot.