Cooking greens and keeping the color
I love greens. Chard, kale, beet, mustard... they're all great accompaniments to a piece of chicken, steak, or fatty pork. But I don't love how ugly they can end up looking after they're cooked. I used to start them out relatively early and sautee them down quite a bit in olive oil and bacon fat, but they'd invariably end up browning and looking awful. My solution has been to basically cook them off last minute before plating so that they cook long enough to soften but don't completely wilt. This usually works, but it can be a pain if I'm trying to keep my eye on other things, and if I hold them for five minutes longer than I intended they can end up looking sad. If I add acid (usually sherry or balsamic vinegar, or lemon juice) I do it a minute or two before serving. Are there any tips for keeping the color on greens? Should I blanch them and do an ice bath before sauteeing them? Is there some magic I could perform using acid or alkaline to keep them looking fresh? Or is the solution to cook them off at the very last second so they don't lose their vital color?
Also any tips for keeping sous vide rainbow chard stems looking fresh and sexy would be appreciated.