Arrange the bacon in a single layer on a large rimmed baking sheet. Bake until browned, 10 minutes. Add the brussels sprouts in a single layer; sprinkle with salt and pepper. Roast until they begin to brown, about 15 minutes.
Remove from the oven, add the apple and toss together. Return to the oven; roast until the brussels sprouts are browned and tender and the apple has softened, 10 to 15 minutes.
Toss the vegetables with vinegar, and serve immediately.
Notes
This recipe is gluten-free adaptable. Be sure to use a brand of bacon that is known to be GF.
Leave apple peels on for added color and nutrition.
This recipe as written turns out brussels sprouts that are not super moist and tender (since they are roasted with no oil). You may wish to toss them in a little bit of oil or at least spray them with cooking spray before roasting if you'd like a different consistency. Add calories/fat, as needed.