Salad with Pancetta Crisps, Roasted Brussels Sprouts, and Pear

Preheat oven to 425 degrees, with racks in upper and lower thirds. On a rimmed baking sheet, arrange pancetta in a single layer. Bake on lower rack until golden brown, 10 to 12 minutes. Transfer to a paper-towel-lined plate to drain; set aside. On another rimmed baking sheet, toss Brussels sprouts with 2 tablespoons oil; season with salt and pepper. Bake on upper rack until tender, 18 to 20 minutes, tossing once.

In a large bowl, whisk together vinegar and remaining oil; season with salt and pepper. Add lettuce, pear, and Brussels sprouts; toss to combine. Divide among four serving plates, and top with ricotta salata and pancetta.