Preheat oven to 425F.
Heat a large skillet over medium-high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Add pancetta and cook until rendered two-thirds of the way. Add the sprouts to the pan and toss.
Spread the sprouts and pancetta on a baking sheet, cut-side down. Roast until outer leaves are brown and crispy and sprouts are tender, about 10-12 minutes.
Top with balsamic drizzle and serve.