Preheat oven to 350°F. Slice pumpkin in half and remove seeds. Rub cut side with olive oil and place (cut side down) on an oiled, rimmed, baking sheet. Roast until tender. Let cool.

Scrape flesh from pumpkin, placing it in the center of a clean piece of muslin or lint-free dish towel. Squeeze out as much liquid as possible.

Toast walnuts in a heavy-bottomed skillet over medium heat, stirring often, until lightly browned, 10 minutes. Remove from pan and let cool. Chop coarsely.

In a medium bowl, mix pumpkin, walnuts, flour, Pecorino Romano, and salt and pepper to taste. Add egg and nutmeg and stir in. Refrigerate at least one hour to make dough easier to handle.

Place breadcrumbs in a shallow bowl. Roll dough into walnut-size balls and dredge in breadcrumbs. Place on baking sheet and refrigerate at least 1 hour.

Simmer in salted water for about 15 minutes or until cooked through. Serve with your favorite pasta sauce.