Gratinata Sauce: Sauté butter, garlic, and rosemary until garlic begins to brown. Add Marsala wine and reduce by one-third. Add remaining ingredients and reduce by half of original volume. Set aside.
Penne Rustica: Sauté pancetta until begins to brown. Add butter, shallots, and shrimp. Cook until shrimp are evenly pick but still translucent. Add chicken, salt, pepper, and mix thoroughly. Add granita sauce and 1/2 cup of parmesan cheese and simmer until sauce thickens.
In a large bowl, combine shrimp and chicken mixture with precooked pasta. Place this mixture into single serving dishes or one large casserole dish. Top with remaining cheese and pimientos and sprinkle with paprika. Bake at 475° F for 10 to 15 minutes. Remove and garnish with fresh rosemary sprig.
Makes: 6