This recipe is totally based on Thomas Keller's recipe from his book Ad Hoc at Home. If you have never roasted collards or any other green, I highly recommend it. Pot-roasting them add a dimension not possible by simmering with water. The flavor becomes deep and resonant. —thirschfeld
collard greens, stems removed and leaves chopped into 1-inch squares, then rinsed twice and dried
Place a heavy-bottomed pot or Dutch oven (with a tight-fitting lid) over medium heat. Add the bacon and let it start to render, then add the butter.
Once the butter has melted, add half of the greens. Season them with a heavy pinch of salt and freshly ground pepper. Stir and turn under the greens so they are coated with fat. Add the rest of the greens and repeat the seasoning and turning.
Cover the pot with the tight fitting lid and slide it into the oven. Roast for 1 hour to 1 hour and 15 minutes. Remove from the oven, remove the lid, and stir. Taste and adjust the seasoning. Put the lid back on and let the collards set until ready to serve.