How to Make It
Melt 1 tablespoon of the butter in a medium skillet over medium heat. Add the onion, ½ teaspoon salt, and ¼ teaspoon pepper and cook, stirring occasionally, until soft, 4 to 6 minutes. Add the cream and simmer until thickened, 5 to 7 minutes.
Meanwhile, heat the remaining tablespoon of butter in a large skillet over medium heat. Add as many collard greens as will fit, season with ¼ teaspoon salt, and cook, tossing frequently and adding more greens when there is room, until wilted, 6 to 8 minutes. Add the cream sauce and toss to combine.