Prep your dish: Use a small, oven-safe baking dish that fits in your air fryer basket (about 7–8 inches). Lightly grease it with butter or spray.

Slice the potatoes: Peel if you like, then slice very thin—about 1/8 inch (3 mm). A mandoline makes this easy and ensures even cooking.

Make the sauce: In a small saucepan, warm the cream and milk with butter, garlic, onion, thyme, 1/2 teaspoon salt, and 1/4 teaspoon pepper. Heat until steaming, not boiling. This infuses flavor and helps the bake set.

Layer the potatoes: Add a thin layer of potato slices to the dish. Sprinkle a pinch of salt and pepper, a small handful of shredded cheese, and a spoon or two of the warm cream mixture. Repeat until you’ve used everything, finishing with cheese and a light dusting of Parmesan and paprika.

Cover for the first stage: Cover the dish tightly with foil. This traps steam so the potatoes soften. Place in the air fryer.

Air fry to soften: Cook at 350°F (175°C) for 20 minutes.

Uncover and brown: Remove foil and continue cooking at 375°F (190°C) for 10–15 minutes, until the top is golden and the potatoes are fork-tender. If your air fryer runs hot, check after 8 minutes.

Rest before serving: Let it sit 5–10 minutes. This helps the layers set and makes slicing cleaner.

Taste and finish: Sprinkle with a little fresh thyme or chives. Add a pinch of salt if needed.