Preheat the oven to 350 degrees F.
In a bowl, toss the bread with the olive oil. Add 3 tablespoons of the cheese and a pinch of salt and pepper and toss to coat the bread evenly.
Place on a baking sheet and bake until browned, stirring occasionally, 10 to 15 minutes. Remove from the oven.
In a skillet, melt 1 tablespoon of the butter over medium-high heat. Add the walnuts and cook, stirring, until fragrant and lightly toasted, 2 to 3 minutes. Add the sugar and Essence, and cook, stirring, until the sugar is caramelized and the nuts are evenly coated, about 2 minutes. Remove from the pan and spread on a waxedpaper lined plate. Separate with a fork and let cool.
Add the remaining 2 tablespoons of butter to the pan and add the sliced apples. Cook, stirring, until lightly caramelized on both sides, about 5 minutes. Remove from the pan.
In a small bowl, whisk together the apple cider, vinegar, and mustard. Slowly drizzle in the oil, whisking constantly until it emulsifies. Add the shallots, salt, and pepper, and adjust the seasoning, to taste.
In a large bowl, combine the lettuces, prosciutto, and croutons and toss with enough dressing to lightly coat. Adjust the seasoning, to taste. Place the apples in a small bowl and add enough dressing to coat.
Divide the lettuces among 6 salad plates and arrange the apple slices on top. Sprinkle the walnuts and remaining cheese over the apples. Sprinkle with freshly ground black pepper and serve.
Yield: 6 servings