If you only like a little bit of heat, use a jalapeno, but scrape out its seeds and white ribs and mince it. If you want four stars, use a couple of Serrano peppers and slice them into rings, leaving in the seeds.
*I added the greens sequentially in order of how long I thought they would take to be cooked to my liking. I added the collards first, giving them 10 minutes total. I thought the chard would be done after 4 minutes, so I added it 6 minutes after the collards. Turnip and mustard greens will take about the same time as chard. If I had been using spinach, I would have only given it about 1½ minutes.