Prepare the potatoes. Butter the bottom and sides of an 8x8” baking dish. Reserve any remaining butter. In a small bowl or on your chopping board, combine the thyme and parsley. Starting on the outer edge of the dish, begin to layer the potato slices with each slice slightly overlapping the one before it. Do this by lining the outer edge, then begin to spiral inward toward the center of the dish with each slice until the layer completely covers the bottom. Sprinkle the layer evenly with a small pinch of salt and a pinch of the herb blend. Continue with the next layer of potatoes and repeat the pattern until you run out of potatoes, then sprinkle the remaining herbs over the top with a pinch of salt.
Prepare the sauce. In a large bowl, whisk the sour cream and Hungarian paprika until blended then whisk in the heavy cream. Gently pour the sauce over the potatoes. Jiggle the dish a bit so the sauce seeps into the layers.