Steak with Creamy Au Gratin

1.Prepare the Au Gratin Potatoes: Preheat oven to 190°C (375°F). Grease a 9x13 inch baking dish with butter.

2.In a large saucepan, combine heavy cream, milk, minced garlic, nutmeg, 1 teaspoon salt, and 1/2 teaspoon pepper. Bring the mixture to a gentle simmer over medium heat, stirring occasionally. Remove from heat.

3.Layer the Potatoes: Arrange one-third of the thinly sliced potatoes in an even layer in the prepared baking dish. Sprinkle with one-third of the Gruyère and Parmesan cheeses. Repeat the layering process two more times, ending with a final layer of cheese.

4.Pour the warm cream mixture evenly over the potatoes and cheese. Gently press down on the potatoes to ensure they are submerged in the liquid.

5.Bake the Potatoes: Cover the dish loosely with aluminum foil and bake for 45 minutes. Remove the foil and bake for another 20-30 minutes, or until the top is golden brown, bubbly, and the potatoes are tender when pierced with a fork. Let rest for 10 minutes before serving.

6.Prepare the Steak: Pat the steaks dry with paper towels. Season generously on all sides with coarse salt and black pepper.

7.Heat the olive oil in a large cast-iron skillet over high heat until shimmering and just starting to smoke.

8.Sear the Steaks: Carefully place the steaks in the hot skillet. Sear for 3-4 minutes per side for a medium-rare crust. Reduce the heat to medium.

9.Baste the Steaks: Add the butter, rosemary sprigs, and smashed garlic to the skillet. Tilt the pan and use a large spoon to continuously baste the melted butter mixture over the steaks for 1-2 minutes, until they reach the desired internal temperature (e.g., 57°C/135°F for medium-rare).

10.Rest and Serve: Remove the steaks from the skillet and place them on a cutting board. Tent loosely with foil and let them rest for 5-10 minutes before slicing against the grain. Serve immediately alongside the hot Au Gratin Potatoes.