I'm sure that this is blindingly obvious to everyone, but yesterday my brain just wouldn't go here.
Any decent stock / wine / cider / juice or whatever based cooking liquid can be turned into a sauce at the end by adding flour, or tipping it out and making a basic roux, then adding the liquid back through the lid, possibly adding a bit of cream / non dairy milk or whatever to ring the changes.
This means that any kind of meat / fish can be cooked with veggies in the varoma while pasta / potatoes / rice / quinoa are cooked in the basket, and the sauce is the cooking liquid which is thickened and possibly enriched at the end.