Combine all of the salad ingredients in a large serving bowl and refrigerate.
In a small bowl, combine the fruit zest, fruit juice, shallot, Dijon and sugar. Whisk to combine. Slowly drizzle in the olive oil while whisking. Season to taste with salt and pepper.
Toss the salad with the vinaigrette and serve at once.
Recipe by Culinary Thymes at https://www.culinarythymes.com/endive-with-apples-walnuts-and-blue-cheese/