Each of these peppery chicory leaves contains multitudes of flavors and textures. They cradle crisp apple slices, tangy pomegranate arils, nutty Gouda shavings, and buttery walnuts, all tossed with a delicate sherry vinaigrette.
Preheat oven to 325°F. Place nuts on a rimmed baking sheet and drizzle lightly with a little oil; season with salt and toss to coat. Toast until golden and fragrant, 14 to 16 minutes. Let cool completely, then roughly chop.
Whisk together vinegar, sugar, and Dijon; season with salt and pepper. Whisk in 1/4 cup oil to make the dressing. Toss 1/4 cup dressing with chicories, apple, pomegranate arils, and toasted walnuts. Season with salt and pepper. Just before serving, top with cheese; serve with remaining dressing alongside.
To mellow the bitter bite of radicchio, you can soak the leaves in cold water for 10 minutes, then dry with a salad spinner before using.