When I've made this, I've cooked the pasta al dente. Adam and Eric said it tasted like your Grandma's with it being cooked. I made it with uncooked pasta too and it wasn't right. The rings are hard to find in CA. Twila brought me out some at Sara's wedding. If anyone needs a box, please let me know. And a whole box is too much pasta. But please feel free to try both ways. I never ate it because I don't eat shrimp so I can only go off my memory of watching your Grandma cook it and what people say it tastes like.
Combine all ingredients together, adding the shrimp last. Keep refrigerated