- 1 cup walnuts, roughly chopped
- 1 large head escarole, torn into pieces (about 12 cups)
- 1 small red onion, thinly sliced
- 2 ounces Parmesan, shaved (about 1/2 cup)
- 2 tablespoons red wine vinegar
- 1 tablespoon Dijon mustard
- kosher salt and black pepper
- 1/3 cup olive oil
- Heat oven to 375° F. Spread the walnuts on a rimmed baking sheet and toast, tossing occasionally, until fragrant, 8 to 10 minutes.
- In a large bowl, combine the escarole, onion, Parmesan, and toasted walnuts.
- In a small bowl, whisk together the vinegar, mustard, ½ teaspoon salt, and ¼ teaspoon pepper. Whisking constantly, gradually add the oil. Toss with the salad.