Thanks for all the suggestions, they give me a few avenues to follow. And yes, we have a lot of vegetarian customers, which is why I'm looking into this.
I've played around with agar a little, but mostly for japanese type gel desserts. Never tried it like this, although the 'nets tell me people use it for whipped cream. I just don't know about the texture and how long it holds. It works like the cornstarch method, like TheoB says. You heat it in a portion of the cream, add to the rest and chill, then whip.
Pectin does need a lot of sugar and acid to set. BUT... there is a type of pectin that doesn't need sugar to set, it comes with a calcium powder that kicks off the gel. It also doesn't need as much acid
. That might work, and my store carries a brand, so the product has already been vetted. Thanks for the idea siduri.
The tricky thing is that this particular pastry is made by an outside baker. Before I suggest the change, I want to have some realistic (and easy) suggestions.
I think I'll need to experiment first before I make the suggestion. I might have some agar and the no sugar pectin hiding in the back of my cupboard somewhere. I'll post the results, good or bad. I'll freeze it too, just to see what happens.