In a large, heavy skillet, melt the butter over medium-high heat. Add the mushrooms, shallots, salt and pepper, and saute until soft and most of the mushroom liquid has evaporated, about 8 minutes. Add the chicken stock, cream and thyme, and simmer until the liquid has reduced by 50 percent in volume, about 5 minutes. Remove from the heat and stir in the truffle oil. Place 2 potato crisps on each of 4 serving plates. Spoon 1 generous tablespoon of mushroom filling on top, topped with 1 teaspoon of grated Asiago. Continue layering the napoleon so that you have 3 layers of potatoes and 3 layers of mushrooms in all, ending with mushrooms on top. Garnish the top of each napoleon with 3 slices of truffle, and sprinkle of Asiago. Arrange the arugula around the outer edge of the plate and serve.

Preheat oven to 400 degrees F.

Brush 2 large baking sheets well with oil. Arrange the potato slices in 1 layer on the sheets. Brush with the remaining oil, and bake until golden, 12 to 15 minutes, switching the sheets halfway through baking.

Transfer with a spatula to cooling racks. Sprinkle with the Essence and salt, and set aside.

Combine all ingredients thoroughly and store in an airtight jar or container.

Yield: about 2/3 cup