Cut off the brown ends of the Brussels sprouts and cut in half. Mix them in a bowl with olive oil. Pour them on two baking sheets and roast for 25-30 minutes, until crisp on the outside and tender on the inside.
Meanwhile, combine the balsamic vinegar and brown sugar in a saucepan. Bring to a boil, then reduce the heat to medium-low and simmer until glaze is thick and syrupy, about 20 minutes.
Drizzle the balsamic reduction over the roasted sprouts. Sprinkle with dried cranberries and serve immediately.
