I’m trying to prep a Mediterranean vegetable tart for a visit from family - I have gluten free puff pastry (not ideal but it's the only ready made available!) as one relative is coeliac, and I need to make it vegan for another relative, and I can’t tolerate onion due to IBS/FODMAP issues.
If I weren’t eating I’d have used caramelised onions to stick the veg to the pastry (I’ve done this before) but I’m stumped for a vegan and onion free alternative.
Any ideas?