Step 1

Preheat the oven to 400°F

Step 2

Butter an 8 by 8-inch casserole dish using 1 tablespoon of the butter

Step 3

In a small pot, add the heavy cream, ½ teaspoon salt and sage leaves

Step 4

Bring to a simmer and steep for 10 minutes

Step 5

Meanwhile, peel and slice the potatoes 1/8 inch thick on a mandolin

Step 6

Begin to layer the potatoes on the bottom of the prepared dish, overlapping each slice by half

Step 7

When the first layer of potatoes is complete, season with salt and cayenne pepper and sprinkle with a third of the cheese

Step 8

Repeat two more times, ending with a final layer of just potatoes

Step 9

Strain the heavy cream and discard the sage

Step 10

Pour the heavy cream over the casserole, pressing the potatoes down

Step 11

Dot the remaining 2 tablespoons butter in pieces evenly over the top of the potatoes

Step 12

Cover with aluminum foil and place in the oven, lowering the temperature to 350°F

Step 13

Bake, covered, for 40 minutes

Step 14

Uncover and bake 20 minutes more

Step 15

Serve hot