Scrub the potatoes clean and pat them dry. If the skins are in great shape, there is no need to peel them. Alternatively, you can peel the skins off. But I think the skins add so much texture to the final crispy-ness.

Cut a thin slice off the bottom of each potato. Rest them on a cutting board, with a chopstick along either side hugging the potato. Cut slits in the potatoes, leaving the bottom intact. Cut parallel slits into each potato, stopping just before you cut through so that the slices stay connected at the bottom of the potato. Space the slices 1/8-inch to 1/4-inch apart. Slice straight down and when your knife hits the edge of the chopstick, stop slicing. But watch the ends of the potatoes, the outer edge may be closer than you realize!

Arrange the potatoes on a baking sheet or in a baking dish. Brush the potatoes all over with half the fat mixture, including the bottoms of the potatoes.

Bake 30 minutes, then brush with more fat. Make sure you get some of the garlic, which always seems to settle at the bottom. Bake the potatoes for 30 minutes. At this point, the layers will start separating. Remove the pan from the oven and brush the potatoes again with the remaining fat — you can nudge the layers apart if they're still sticking together. Make sure some of the fat and garlic drips down into the space between the slices.

Bake until the potatoes are crispy on the edges and easily pierced in the middle with a paring knife, 20-30 minutes. This will depend on the size of your potatoes. If you're adding any extras, stuff those into the slits and sprinkle over the top 5 to 10 minutes before the end of cooking.

Remove to a serving platter. Sprinkle with the Maldon salt, the Aleppo pepper and chopped herbs. Serve immediately. These potatoes are best straight from the oven while the edges are at their crispiest.