Pat your steaks dry with paper towels, then season both sides generously with salt, pepper, dried thyme, and rosemary. Heat 2 tablespoons of olive oil in a large skillet over medium-high heat. Sear the steaks for 3-4 minutes on each side until a golden-brown crust forms. Remove from skillet and let rest.

In the same skillet, reduce heat to low and add 6 tablespoons of butter along with the minced garlic. Stir frequently for about 1-2 minutes until fragrant, then remove from heat.

Peel and thinly slice the russet potatoes to about 1/8 inch thick. In a large mixing bowl, toss the potato slices with half of the garlic butter and season with additional salt, pepper, and a teaspoon of dried thyme.

Preheat the oven to 375°F (190°C). In a baking dish, layer half of the seasoned potato slices. Slice the rested steaks and lay them on top, followed by half of the cheddar cheese. Repeat the layers and drizzle the rest of the garlic butter on top.

Cover the baking dish with foil and bake for 40 minutes. Remove the foil and bake for an additional 15 minutes until cheese is bubbly and golden.

Let the casserole rest for 5-10 minutes before serving to allow flavors to meld.