Start by preheating your oven to 425°F. This high heat will ensure a crispy skin on your potatoes.
Place a potato between two chopsticks or wooden spoons to act as a guide, preventing you from slicing all the way through. Carefully make thin slices about 1/8 inch apart. Repeat with all the potatoes.
In a small bowl, whisk together the olive oil, melted butter, minced garlic, dried thyme, salt, pepper, and paprika. Brush this mixture generously over and between the slices of each potato.
Arrange the potatoes in a single layer in a baking dish. Bake in the preheated oven for about 50-60 minutes, or until the potatoes are golden and crispy. Halfway through, baste the potatoes with the oil and butter mixture pooled at the bottom of the dish for extra crispiness.
Once done, let the potatoes rest for a couple of minutes. Sprinkle with fresh thyme leaves and a pinch of flaky sea salt for an extra burst of flavor and texture.