3 lb. mixed bell peppers and chiles
6 garlic cloves, lightly crushed
⅓cup extra-virgin olive oil
Kosher salt, freshly ground pepper
12oz. fresh mozzarella
Basil leaves (for serving)
1 Tbsp. white balsamic vinegarThe best cookie I've had in years. Thank you! –Jane Williams
Preheat oven to 325°. Toss peppers, chiles, garlic, and oil in a Dutch oven or heavy roasting pan; season with salt and pepper and toss again to coat. Cover and roast, tossing occasionally, until peppers are very tender, 2–2½ hours. Let cool.
Arrange half of peppers on a platter. Top peppers with mozzarella and basil. Measure out 3 Tbsp. of the oily juices left behind and transfer to a small bowl (save remaining peppers and their juices for another use; we love them tossed with pasta, layered into sandwiches, or stirred into frittatas). Add vinegar; season with salt. Stir to combine, then drizzle dressing over salad.
Do Ahead: Peppers can be roasted 1 week ahead. Cover and chill.