In the wake of rising food prices around the world, the United Nations proclaimed the spud one super-nutritious value.

To hammer the point home, the U.S. Potato Board has begun the "Potatoes: Goodness Unearthed" campaign to remind consumers that despite the contempt of the Atkins era for the starchy vegetable, a medium spud has only 110 calories, is naturally fat-free, high in vitamin C and - when eaten with the skin on - packs more potassium than a banana.

One of the easiest ways to prepare potatoes is to mash them, but the addition of butter, milk and cream certainly adds fat and calories.

As an alternative, try Mashed Potatoes With Celery Root. It gets its creaminess from plain yogurt and a boost of flavor from celery root, a root vegetable that tastes like a cross between strong celery and parsley. Shrouded in a gnarly tangle of thick, hairy skin, celery root requires a bit more patience to peel than a potato, yet the creamy flesh is easily transformed into a puree of beauty.

Celery root is in season now through April and adds small amounts of vitamin B, calcium and iron to mashed potatoes.

Celery root has many names, including celeriac, celery knob, turnip rooted celery, and knob celery. Avoid roots that have soft spots and check for mold or signs of spoilage. Store the root in a plastic bag and refrigerate no more than 7 to 10 days.

Some people enjoy eating potato skins for their taste and their potassium content, and you can leave them on for this recipe. But the skin of celery root must be removed and is not easily stripped with a vegetable peeler.

Cook's Illustrated suggests the following: Cut off about 1/2 inch from each end of the celery root so it rests flat on a cutting board. To peel, simply cut from top to bottom, rotating the celery root as you remove wide strips of skin. Cut down through the peeled root to create slices. Stack the slices and cut into strips, and cut again into 1/2-inch pieces.

Mashed Potatoes With Celery Root

Makes 6 to 8 servings

2 pounds Idaho potatoes, peeled and cut into 1/2-inch pieces

3/4 pound celery root, peeled and cut into 1/2-inch pieces

2 cloves garlic

1/2 to 3/4 cup plain yogurt

Salt and pepper to taste

Minced chives, optional, for garnish

1. Place potatoes, celery root and garlic in a large saucepan. Cover with water. Bring to a boil over high heat. Reduce heat to a simmer and cook 15 minutes or until potatoes are tender.

2. Drain and mash with a potato masher. Midway through mashing, add yogurt, then continue to mash until smooth. 3. Season with salt and pepper, to taste. Sprinkle with chopped chives before serving if desired.