Start off by preheating your oven to 375°F (190°C).
In a saucepan, melt butter and sauté minced garlic until fragrant.
Layer half of the thinly sliced potatoes in a greased baking dish.
Next, sprinkle half of the cheddar and Parmesan cheese over the potatoes.
Pour half of the heavy cream over the cheese layers and season with salt and pepper.
Now, repeat the layering process with the remaining potatoes, cheese, and cream.
Bake uncovered for 60-70 minutes, or until the potatoes are tender and the top is golden brown.
Garnish with fresh thyme before serving. Enjoy.