Using a mandoline slicer has proven to be painful if you get a bit distracted. My daughter will vouch that I’m like a magpie – easily distracted by shiny objects. Only this time my distraction was dull (unlike my mandoline) and a shade darker. Making scalloped potatoes was probably a bad idea. —All that's Jas
Peel, wash, and cut the potatoes into very thin slices using mandoline slicer or a knife.
Heat the heavy cream, milk, and butter over medium-high heat until the butter is melted. Season the cream with salt.
Grease a baking dish with butter. Layer the potato slices into the baking dish. Pout the cream sauce evenly over the potatoes. Add fresh thyme leaves or sprigs if desired. Bake, covered for 1 hour, then uncover and bake 30 minutes longer or until tender. Sprinkle with freshly ground black pepper before serving.