I would start a creme brulee recipe with FlavourArt's Vienna Cream flavor. It's creamy, sweet, vanilla, and eggy - sort of like a plain, unspiced eggnog. To 2-3% of that (it's a strong flavoring) I'd add a favorite caramel (EDIT: or a tiny bit, maybe 0.5 or 1%, of TFA Brown Sugar Extra) for the baked top, maybe a sprinkle of cinnamon or nutmeg, extra vanilla if you like.
(EDIT yet again: Wow, I'm just not thinking clearly today! It would be easier to start with FA Catalan Cream, which IS a creme brulee flavor. There's a little caramel and tiny bit of spice already in it, but of course all the additions I mention above might be ones you'd like. Here:
http://www.bullcityvapor.com/catalan-cream-fa/