Slice the potatoes super thin, about 1/16 of an inch thick. You can leave the skin on since they're sliced so thin it won’t be noticeable. Use a mandoline slicer for even, paper-thin slices; a knife won’t get them thin enough.

Soak the potato slices in ice water for at least 30 minutes. This helps remove excess starch so the chips don’t stick together and will crisp up during frying.

After soaking, drain the slices and lay them in a thin layer on paper towels. Blot off excess moisture to prevent dangerous oil splatters.

If using a cast iron skillet, pour in enough beef tallow to reach about a ½-inch depth of oil. This usually requires about 3 cups in a large skillet. If you have a deep fryer, follow its manufacturer’s instructions.

Heat the tallow until it is shimmering and just starting to smoke. Carefully slide the potato slices into the oil one at a time from the side of the skillet to avoid splashing. Do not overcrowd the pan; the slices should not overlap so they fry evenly and are easy to flip.

Fry the chips, watching closely. When the edges start to turn golden, flip them over. They finish frying quickly—less than 30 seconds after flipping. Remove from oil as soon as they are golden brown to avoid burning.

Line a bowl with a paper towel to catch excess oil. Use a slotted spoon to remove the chips from the oil, letting the oil drain briefly before placing them in the bowl. Sprinkle with salt while the chips are still hot for best adherence. Repeat the process with the remaining potato slices.