How to Make It
Heat oven to 350° F. On a rimmed baking sheet, toss the bread with 2 tablespoons of the oil. Bake until golden and crisp, 14 to 16 minutes.
Whisk together the remaining 1/3 cup oil, the vinegar, ¼ teaspoon salt, and ½ teaspoon pepper in a large bowl. Add the arugula, chicken, mozzarella, roasted red peppers, and bread and toss to combine.