Preheat oven to 425 degrees.
Cut the sprouts in half and place on a large rimmed baking sheet. (Cut side facing down)
Drizzle with olive oil and season to taste with salt and black pepper.
Roast for 12 minutes.
Remove from the oven and immediately toss with the 2 tablespoons butter and the bacon.
Transfer to a serving platter and top with freshly grated Parmesan cheese.