• Make-Ahead

Ingredients

1. 2 sticks (1/2 pound) unsalted butter
2. 3 large celery roots (4 1/2 pounds)—halved, peeled and coarsely chopped
3. Salt and freshly ground pepper
4. 8 Granny Smith apples, peeled and coarsely chopped
5. 3/4 cup verjus (see Note) or dry white wine
6. 2 tablespoons sugar
7. 1 star anise pod
8. 2 cups baby spinach leaves

Directions

1. Melt the butter in a very large, deep skillet. Add the celery roots and cook over moderately low heat, stirring occasionally, until starting to soften, about 10 minutes. Season the celery root with salt and pepper. Add the chopped apples, verjus, star anise pod and sugar. Cover and cook over low heat, stirring occasionally, until the celery root and apples are very tender, about 30 minutes.
2. Discard the star anise pod. Working in batches, in a food processor, puree the celery root and apples with the raw spinach. Season with salt and pepper and serve hot.

Make Ahead

The celery root and apple puree can be refrigerated overnight. Rewarm the puree over moderate heat, stirring frequently.

Notes

Verjus, the juice of unripe grapes, has a tart, applelike flavor. You can buy it at specialty markets. The F&W Test Kitchen especially likes the verjus from Wölffer Estate (wolffer.com).