For cauli, brocolli, zucchini, corn, we blanch in boiling water for 30s or so, then drop into iced water. Remove, allow to cool/drain, and then vacuum seal in bags. If they're going to be grilled on the BBQ, we add marinade before sealing in the bags.
For spinach, kale, silverbeet, we boil/steam until soft, drain, squeeze out extra moisture and then vacuum seal, to be chopped and added to quiche, pasta or whatever.
Artichokes we peel and prepare in regular artichoke fashion, boil for a few minutes, then cool and vacuum seal in a bag with marinade (soy sauce, garlic etc), ready for the BBQ.
So I guess all of ours are at least par-cooked before freezing.