low-glycemic mash for Thanksgiving, tried

Cauliflower -- boiled gently, mashed.
Turnip -- braised w/butter, lemon slice, bay (I use California bay, so a fraction of a leaf: French bay would be a whole leaf, maybe), pick out lemon and bay, mash with cauliflower.
Cream.

Period.

You could do other things. You could add other herbs. Parsley, notably, because parsley is wonderful. If you don't know parsley is wonderful, either you haven't had it fresh and flat-leaved, or you're a supertaster and there's nothing to be done for you, poor dear.

Proportion: three times as much cauliflower to turnip, though I do not think this is urgent.

I tried this because every time I eat a potato or grain thing I can't stop eating, or I get heartburn, or digestive upset, or a headache, or I can't sleep at night. Or some combination up to all three. And the next day I feel like I've gained ten pounds (but I only gain two or three) and my joints are going to give out.

It looks like "grains in moderation" is just not in the cards.