Preheat the oven to 425°F (218°C).
Remove the outer layer of the Brussels sprouts and discard the dirty leaves. Trim the end off of each sprout and then slice in half vertically.
Put the sprouts in a large bowl, a large (14 to 19-incskillet, or on a parchment lined (optional, but makes for easy clean-ubaking sheet and drizzle the 3 tbsp of olive oil and 2 tbsp of vinegar over the sprouts. Salt and pepper to taste and then toss until the sprouts are coated with the oil and balsamic.
Spread them evenly out on the pan flat side down. You don’t want them to touch or they’ll end up steaming instead of roasting.
Roast for 15 minutes and then shake the pan and roast for another 15, or until they’re caramelized and the edges are crispy. (SEE NOTE)
Drizzle the remaining 1 tbsp of balsamic over the sprouts and toss.
Best when eaten hot.