Ingredients

3 medium sweet potatoes (about 1 pound each)

3/4 cup low-fat cottage cheese

3/4 cup diced Fuji apple (skin on)

3 tablespoons chopped fresh chives

1 piece (2 ounces) Parmesan cheese, half grated and half shaved

1/4 teaspoon coarse salt

Freshly ground pepper, to taste

Vegetable-oil cooking spray

1 tablespoon walnut oil

1/3 cup chopped toasted walnuts (about 1 ounce)

Preparation

Preheat oven to 375 degrees. Wrap 1 sweet potato in parchment, and then in foil. Pierce several times with a fork. Bake until tender, about 1 hour. Let cool. Reduce oven temperature to 350 degrees.

Meanwhile, peel remaining sweet potatoes. Using a mandoline or a chef’s knife, cut potatoes lengthwise into very thin slices until you have 30 slices. Trim each to a 2-by-4-inch rectangle.

Bring a large pot of water to a boil. Add half the sweet potato slices, and cook until tender, about 2 minutes. Using a slotted spoon, place slices on a baking sheet to cool slightly. Repeat.

Remove peel from baked sweet potato, and puree flesh in a food processor until smooth. Add cottage cheese, and puree until smooth.

Transfer potato-cheese mixture to a large bowl. Stir in apple, chives, grated Parmesan, salt, and pepper.

Coat a 9-by-13-inch baking dish with cooking spray. Place 1 heaping tablespoon filling in center of a sweet potato slice, and roll up. Place, seam side down, in dish. Repeat. (Cannelloni can be refrigerated, covered, overnight; bring to room temperature before baking.)

Brush oil over cannelloni. Bake until heated through, 10 to 15 minutes. Sprinkle with walnuts and shaved Parmesan.