Preheat oven to 400 degrees. Place the Brussels sprouts on a baking sheet (I line with parchment paper), including some of the loose leaves. Add the pancetta, olive oil, salt, and pepper. Mix together with a spoon (or you can use your hands).

Roast the Brussels sprouts for 25-30 minutes, until they’re tender and nicely browned and the pancetta is cooked. Rearrange on the baking pan once during roasting.

Remove from the oven, drizzle immediately with the balsamic vinegar, and toss again. Salt and pepper to taste and serve!