Recipe Request - Mushroom custard

Has anyone ever made a mushroom custard?
Saw this fluffy hen-of-the-woods mushroom custard served warm with crumbled marcona almonds and shaved Parmigiano-Reggiano on Atlanta Cuisine (right click to open in new window) and the photo makes me drool.
I'd love to make it this weekend - but using oyster mushrooms as I don't have hen-of-the-woods.
We may even have some of our own field mushrooms to use - if the bugs don't get to them first. Picked our first crop a couple of weeks ago, when they popped up after some rain.

I'd adapt something like this, but using a mushroom broth. Hen-of-the-woords (maiitake) is much stronger in flavor than oyster, so use some porcini soaking liquid or something like that to pump up the flavor. The side there looked like a pretty simple sautee/deglaze.

Yikes, what a lot of eggs and cream, but I guess I should have realised with custard.
Usually have to go to a specialty store to get dried Porcini. Porcini Powder seems to be the new vogue. I really should get a jar for the cupboard next time.