Shrimp fettuccine alfredo is best served immediately, as the texture of the sauce changes once cooled. If storing in the fridge, separate into individual bowls equivalent to the serving size you'll eat later. Reheat in the microwave until warmed through, stirring between 1 minute intervals. Note that the alfredo sauce will not be the same smooth and creamy sauce it was before, and instead will be a little chunkier.