Core, and dice the apple, toss it with a splash of apple cider vinegar to prevent browning
Cut the brussels sprouts in half
Cut the bacon into small pieces and cook in a nonstick pan on medium heat for 6-7 minutes or until browned and crispy, stirring occasionally
Transfer the bacon to a paper-towel-lined plate, leaving the fat in the pan
Add the brussels sprouts and apple to the still hot bacon fat and season with salt and pepper. Toss to coat thoroughly, adding a little more olive oil if the pan is too dry.
Transfer the mixture to a baking sheet and roast in the oven for 9-11 minutes, or until browned and caramelized.
Transfer to a bowl and mix in the remaining vinegar and the bacon pieces and stir together
