Yay! We did that and it was a lot of fun. Actually our scenario was a bit complicated - DH wanted to find out and then surprise me with a colored cake from a bakery that I would cut into, but we couldn't find a bakery that would dye the cake.
DH then offered to make the cake himself, which I imagined as a disaster, so in the end, I made two cakes!! A pink and a blue. Then iced with white, left a little peeking out so DH could identify. He picked the cake based on what he knew from the tech, iced the rest, presented to me, and took a vid of me cutting into the blue cake.