Prep: 1. Chop bacon. 2. Remove stems from collard greens. 3. Chop onion. Make: 1. In a large pot or Dutch oven, cook bacon over medium until just browned. Add onion and cook, stirring often, until softened, about 3 minutes. 2. Add a dollop of Dijon mustard; stir for 1 minute. Add collard greens. Stir until wilted. 3. Add chicken broth (it should almost cover the greens) and salt and pepper. Cover and simmer over medium-low, stirring occasionally, until greens are very tender, about 45 minutes. 4. Remove from heat and stir in a spoonful apple cider vinegar. Season with salt and pepper to taste.