Indulge in Potato Gratin with Sage and Parmigiano Reggiano. Preheat oven to 350ºF. Peel and slice 3 lbs Yukon gold or red potatoes, layering them in a 12-inch skillet with ½ cup thinly-sliced onion, sprinkling 3 tsp kosher salt as you go. Pour 3 cups heavy cream, add ¼ tsp black pepper, ⅛ tsp nutmeg, and 6 sage leaves and gently stir. Simmer on medium-high heat, then low for 15 mins till cream thickens and potatoes are half-cooked. Dot with 1 tbsp unsalted butter and sprinkle ⅓ cup Parmigiano Reggiano. Bake until cheese is golden, and potatoes are tender, about 15 minutes. Enjoy!