Celery root and fennel add both flavor and a touch of sophistication to a classic dish -- potatoes au gratin.

Celery Root, Potato and Fennel Gratin

1 large celery root, about 1 pound, peeled and thinly sliced
2 baking potatoes, like russets, peeled and thinly sliced
2 fennel bulbs, thinly sliced
1/2 cup all-purpose flour
1 teaspoon salt
1/4 teaspoon freshly ground black pepper
4 cups milk

1/4 cup melted butter
12 ounces (3 cups) shredded Swiss cheese

1. Preheat oven to 350°F (175°C). Lightly butter a 3-quart baking dish.
2. Place the celery root, potatoes, and fennel in a large bowl and toss to combine.
3. In a large measuring cup, combine the flour, salt, and pepper. Whisk in the milk and butter.
4. Layer 1/3 of the vegetables in the prepared baking dish. Sprinkle with 1/3 of the cheese. Repeat layering, reserving the last 1/3 of the cheese.
5. Pour the milk mixture over all, pressing the vegetables down to cover. Sprinkle the remaining cheese on top.
6. Bake for 1 hour, or until the vegetables are tender.

Makes 8 servings.