Preheat oven to 400 degrees Fahrenheit (200 degrees Celsius) and grease a 9x13-inch baking dish.
Heat olive oil in a large skillet over medium-high heat and sear the steak cubes until browned on all sides, approximately 3-4 minutes.
Place half of the sliced potatoes in an even layer at the bottom of the prepared baking dish.
Distribute the seared steak cubes, diced onion, and minced garlic evenly over the first potato layer.
Arrange the remaining potato slices over the steak and onion layer.
In a mixing bowl, whisk together heavy cream, beef broth, salt, pepper, and dried thyme.
Pour the cream mixture evenly over the contents of the baking dish.
Cover the dish tightly with aluminum foil and bake for 40 minutes.
Remove the foil, sprinkle the shredded cheddar cheese over the top, and bake uncovered for an additional 10 minutes until the cheese is bubbling and golden.
Remove from oven and let rest for 5 minutes before serving to allow the sauce to set.