Preheat the oven to 400°F (200°C). In a bowl, toss the walnuts with the oil and salt. Spread the walnuts in a single layer on a rimmed baking sheet, place in the oven, and toast for about 15 minutes, or until they take on color. Let cool.
Separate the endive leaves and divide them among 4 plates. You can place them casually or stack them like a game of Jenga. Next, add a handful of the matchstick-cut apples to each salad, followed by a handful of the walnuts. Crumble the Stilton and sprinkle it on top. Finally, add the chives, some dressing, and a twist of pepper.