Ingredients

• 4 tablespoons unsalted butter
• 1 small yellow onion
• 4 garlics cloves
• 1.5 cups heavy whipping cream
• 1 , 12 ounce
• 0.5 teaspoons kosher salt
• 4 pounds Yukon Gold potatoes
• 0.5 cups Parmigiano-Reggiano cheese
• 1 tablespoon freshly ground black pepper
• 2 cups pecorino Romano cheese
• fresh thyme leaves , for garnish

Instructions

1. 1 Gather all ingredients.
2. 2 Preheat oven to 375 degrees F (190 degrees C). Heat butter in a large 12-inch high-sided skillet over medium heat until melted. Add onion and cook, stirring occasionally, until softened, 5 to 6 minutes. Add garlic and cook, stirring constantly, until fragrant, about 1 minute.
3. 3 Add cream, evaporated milk, and salt and stir. Add potatoes, separating slices from each other and nestling potatoes in cream mixture until potatoes are partially covered. Bring to a boil over medium-high. Reduce heat to medium and simmer, stirring and folding often, for 15 minutes. (Potatoes will be harder to stir at first but will soften as they cook). Remove from heat.
4. 4 Add Parmigiano-Reggiano, pepper, and 1 1/2 cups of the Pecorino-Romano; fold and stir until potatoes are evenly coated in cheeses. Top evenly with remaining 1/2 cup Pecorino-Romano.
5. 5 Cover tightly with foil and bake in preheated oven until potatoes are fork tender, 35 to 40 minutes.
6. 6 Remove foil and increase oven temperature to broil. Broil until cheese is golden brown, 4 to 5 minutes.
7. 7 Remove and let sit for 10 minutes. Garnish with thyme and pepper and serve.

Nutrition per serving