Gender reveal party for two - ideas??

Hi guys, me and my partner and finding out the gender in 2 weeks, and instead of a sonographer telling us the gender, we would like to make a small party/dinner for two, where we would discover the gender. We are going to ask them to write it on a piece of paper and put it in the envelope, but I have no idea of how to work it out later and make it fun! Doesn't have to be anything grand, we are also not planning to order the while cake for this as it's just for the two of us, but looking for some ideas on how to make it a surprise for us !! :))