I recently had an affair with yuzu. A terrific few months, but then I realized I was paying for everything! I'm embarrassed to say how much I spent on those teeny bottles of yuzu juice. It is a very unique flavor, but I do think it is subtle and maybe not worth using large quantities in a cake. Primarily I used it in iced tea: a fruity tea, just a little simple syrup and dash of yuzu. I have weaned myself off it and gone back to using lemon in my iced tea. It was a painful break-up but it was emptying my retirement reserves.
I did score some fresh yuzu fruit when it was in season. That season is not now, and it seems very short. It wasn't cheap, either, so I'm thankful for that short season. If I had a load of fresh fruit I would make a posset or custard or maybe a key lime pie subbing in yuzu. That yuzu mayo sounds pretty yummy....
