Preheat the oven to 140°C. Rub the butter all over the surface of a shallow oven proof dish. Peel and finely slice the potatoes. Lay the slices on a clean tea towel and pat dry. Keep them covered with the tea towel while you prepare the rest of the ingredients.
Pour the milk and cream into a saucepan. Add the garlic, thyme and shallot. Slowly heat the milk and, just as it is about to reach boiling point and you see bubbles appearing around the edge of the pan, remove it from the heat. Strain the liquid into a large jug, sprinkle in the nutmeg and keep warm.
Layer half the potato slices in the dish, slightly overlapping the slices and sprinkling with a little salt and freshly ground pepper between each layer.
Pour half the hot milk and cream over the potatoes, then finish off layering the rest of the potatoes. Pour over the rest of the hot milk and cream. Bake for about one hour, until golden and tender. Leave the dish to stand for about 5 minutes, then serve sprinkled with a few fresh thyme leaves.
Fillet Steak: Season the steaks well with salt and pepper. Heat an ovenproof frying pan until smoking. Add a little oil and turn down heat slightly. Add steaks and sear on all sides, cook for 2 minutes each side.
Remove to oven, covering with a butter paper. Finish off for 8 minutes for medium rare. Remove from oven and rest for approx 5 minutes while preparing scallops and spinach.
Wilted Spinach: Wash the spinach 3 times carefully. Shaking off the excess water place in a hot frying pan. Cook on a high heat for a couple of minutes until the spinach is wilted, forking it around a couple of times. Drain, grate a small amount of nutmeg over it, cover and set aside.
Scallops: Dry the scallops on kitchen paper and season. Heat a heavy-based pan, then add the oil. Once hot, add the scallops, keeping them close together.
Sizzle for 2 minutes until caramelized and you can see the heat creeping up the outside. Turn over with a palette knife, then fry for 1 min more. Take off the heat, then add a few good slices of the butter to the pan, spooning over the scallops as it melts.
Assembly: Carefully place steak onto warmed plate. Using a scone cutter, cut some of the potato and place beside the steak. Slice the scallop in two and place a piece of marrow in the middle, flash under the grill and serve on the spinach.