I've lost the original posting, but a few days ago someone asked for ideas on
how to firm up a veggie lasagna. I usually pre-cook the veggie filling in a
non-stick pan, and at the end when everything is mostly cooked, add a mixture
of 2 tbsp cornstarch and 1 tbsp water. This seems to help hold the filling in
just about everything. I use it for savoury pies, calzones, layered
casseroles, etc. Potato starch works too, but without quite as much holding
power.
-Steve.
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