This sophisticated salad with white beans and Italian ham is minutes away.
Preheat oven to 375 degrees. Arrange bread pieces on one side of a rimmed baking sheet; toss with 1 teaspoon oil and season with salt and pepper. Lay prosciutto on other side of sheet. Bake until both are golden brown, 10 to 12 minutes. Let cool completely on sheet. Crumble prosciutto.
In a large bowl, whisk together vinegar and 2 teaspoons oil; season with salt and pepper. Add romaine, croutons, prosciutto, beans, and scallion and toss to combine.
Cut cleanup time by using the same baking sheet to crisp the prosciutto and make the croutons.