Ask the night before. Give them a heads up. 50% 50% chance.
Cruise well and enjoy every moment.
I have to report back on how this worked out! Last night (our first night on board) I ordered the chicken, and asked about getting the raviolo and adding shrimp the next night (tonight). Our server, May Rose, said that was no problem and she would let the chef know.
Tonight we went in to dinner and we weren't seated in May Rose's section, but she came over to us and said everything was arranged and she would let our current server know (Louie). My dinner comes, and guess what? The chef actually made me my own special raviolo with the shrimp INSIDE of it! It was amazing, and I was just so touched that they took the trouble to arrange something special for me, when I would've been happy with just a side plate of shrimp! May Rose came by to see if I liked it and I told her she had just made my entire vacation. 🙂