In a large pan, heat the olive oil over high heat and add the onion, garlic, and pumpkin and cook 1 minute. Add the water, salt and pepper, lower heat to medium and cover, cooking until the pumpkin is soft, about 8 minutes. Add the red pepper flakes and parsley and keep warm.
Bring 6 quarts of water to a boil and add 2 tablespoons salt. Cook the ziti according to the package directions, until tender yet al dente. Toss the pasta with the cooked pumpkin 1 minute over high heat. Divide evenly among 4 warmed pasta bowls, topped with freshly grated Parmigiano-Reggiano.
Recipe copyright 2000, Mario Batali. All Rights Reserved.