The beauty of a custard is that it mixes well with just about anything. Fruits, as mentioned. Tobaccos if you like those flavors. It will also mix ok with most desert flavors, though that makes it a little too sweet for my taste. If you like coffee/cappuccino flavors it also sweetens them up nicely. The only thing I can think of off the top of my head that I don't think it would mix well with are soda and drink flavors, but just because I think that sounds awful doesn't mean you will....who knows, maybe that sounds great to you.