Preheat the oven to 375°F.
Sauté your wild mushrooms to your liking and set aside.
Brush a 13x9x2-baking dish with 2 tablespoons of the olive oil.
Arrange a layer of about 1/3 of the potatoes, slightly overlapping (like fallen dominos) in the dish. Season the potato layer lightly with salt, pepper, thyme and rosemary.
Pour a 1/4 cup of cream over the potato layer and sprinkle with 1/4 cup of cheese on top. Add the sautéed mushrooms on top in an even layer. Sprinkle a little more cheese on top of the mushroom.
Repeat layering 1/3 of potatoes, seasoning lightly with salt, pepper, herbs, 1/4 cup cream, and 1/4 cup cheese two more times.
Bake uncovered until potatoes are fork tender, for about 40 minutes. Remove the pan from the oven and top the potatoes one final time with 1/4 cup cream and 1/4 cup cheese. Bake for 15-20 later until the top has browned nicely.