Method:
Cook pasta in boiling salted water until al dente. While pasta is cooking, cook sausages in a few tablespoons of water over moderately high heat, until water evaporates and sausages are browned and cooked through. When cool enough to handle, slice sausage into 1/2-inch-thick ovals. Transfer sausage to a bowl, reserving drippings in skillet.
Cut broccoli rabe into 1-inch pieces and cook in reserved drippings, stirring occasionally, until it begins to brown. Add garlic and cook, stirring frequently, until lightly browned, about 1 minute. Add broth and raisins and simmer until broccoli rabe is just tender, about 3 minutes. Add butter, stirring until melted and smooth.
Drain pasta and return to pot. Add broccoli rabe mixture and sausage and heat through. Serve with Parmesan.