Cook pasta and shrimp per directions on packages.
While they are cooking, melt 4 tablespoons butter in a small skillet.
Add cream of coconut and bring to a light boil.
Stir in about 1/2 can evaporated milk and bring back to a light boil.
Stir in cornstarch and cook until thickened.
Add additional evaporated milk to thin, if needed.
Stir 1/2 coconut sauce into cooked and drained pasta.
Place a serving of pasta on each plate, top with 3 to 4 shrimp, and serve additional coconut sauce on the side for dipping shrimp.