Make mustard maple glazed bacon if using: Mix mustard and maple syrup together in a tiny bowl, and brush on both sides of bacon. Place on a sheet pan, or a couple pieces of oil, with edges turned up to catch the oil. Bake in a 400 F oven until crispy, about 15-20 minutes. Drain, blot and chill. Crumble with your fingers.
Make dressing: Mix all dressing ingredients together in a small bowl and immediately refrigerate. You want the dressing to be really cold! Feel free to make ahead!
When ready to serve, cut the romaine hearts into long quarters, and lay side by side on a platter. Arrange the remaining veggies, down the center, over the romaine.
Pour the chilled dressing down the center, over the veggies, sprinkle with the crumbled bacon and chives and serve immediately.