Preheat oven to 375 degrees F. Spray a muffin tin with a nonstick spray and set aside.
Melt the butter in a small saucepan over medium eat. Add the garlic. Cook until fragrant, about 1 minute. Add the heavy cream, thyme, salt, and black pepper. Bring to a simmer and cook for about 2 minutes. Remove from heat.
Wash your potatoes, leaving the skin on. Thinly slice the potatoes on a mandolin or with a very sharp knife. Add the potatoes to a large bowl, and pour the cream sauce on top. Toss to coat.
Layer the potato slices in the prepared muffin tin, filling to the top of each muffin mold. Amount of stacks created with vary. I was able to get 10 stacks. Pour any remaining cream sauce on top. Cover tightly with foil
Bake the stacks for 30 minutes, and then remove the foil, add the cheese to each stack, and bake uncovered for 15-20 minutes or until the potatoes are cooked through and the cheese is melty and golden.
Let stand for 5 minutes before serving. Enjoy!