Preheat oven to 400 degrees. Peel potatoes and slice evenly – I highly recommend using a mandolin slicer for this – about 1/8-inch thick.

Combine the cheeses and transfer ¼ to a separate bowl and set aside. Add the cream, garlic, parsley, and thyme to the cheese mixture. Season generously with salt and pepper. Add in potatoes and combine with your hands so that the mixture gets in between each slice of potato.

 Coat a cast iron pan or circular casserole dish with butter. Start by placing potatoes all around the edge with about 1/3 of each potato overlaying the one before. Once the first row is complete, continue to work toward the center of the dish, overlapping each slice. You want the slices to be fairly upright to get the best visual appearance.

Pour some of the excess cream and cheese on top of the potatoes so that it comes up about halfway up the dish. Cover the dish with aluminum foil and bake in the oven for 30 minutes. Remove the foil and bake for about 30 minutes or until the top begins to brown. Sprinkle your set aside cheese on top and bake for about 30 additional minutes or until the cheese is golden brown. Let it rest for a few minutes before serving.