bread & butter pud - bain marie/directly in the oven?

[AuldAlliance]

I'm trying to use up a not v nice panettone (get me, eh?), and thought I'd make a variant of bread & butter pudding with it.
But all the recipes I've found say to cook it in a bain marie.
We currently only have a small combination microwave/fan oven, which I can't fit a roasting tin in.
So can I skip the bain marie cooking bit, and just bung my b&b pudding straight in the oven, or will disaster ensue?

I made it last month and didn't cook it in a bain marie. More palava imo and for no difference in taste.

Excellent, thanks! Off to prepare a calorie-ridden pudding...