Preheat your oven to 350°F (175°C).

Using a mandolin, slice the Yukon Gold potatoes thinly to about 1/8 inch.

Melt the butter in a medium saucepan, then whisk in the heavy cream over medium heat until slightly thickened.

Gradually add the Parmesan cheese and thyme, stirring until melted and smooth.

In a greased baking dish, layer the sliced potatoes, seasoning each layer with salt and drizzling cream sauce.

Pour the cream sauce evenly over the layered potatoes.

Bake in the preheated oven for about 1 hour, until golden brown and bubbly.

Let the dish rest for 10 to 15 minutes before serving.