Thoroughly wash the potatoes. Then, using a mandolin set to 1/16 or 1/8th inch, slice the potatoes and immediately transfer to a large bowl of cold water. Ensure the water completely covers the potatoes. Let the potatoes soak for 30 minutes, agitating gently from time to time with your hands.
Meanwhile, line a large tray with paper towels and set a baking/cooling rack on top.
After 30 minutes, transfer the potatoes to a colander and rinse under cold water. Rinse the large bowl as well. Shake, dry, then return the potatoes to the rinsed bowl. Pour malt vinegar over the potatoes and rest another 30 minutes.
Meanwhile, heat oil in a large deep skillet to about 350-365 degrees.
Once again, drain potatoes then dry them in a salad spinner or by patting them dry between paper towels. Ensure they are as dry as possible before frying.
In batches, add potato slices to hot oil in a single layer and cook for 3-4 minutes, stirring occasionally with a slotted spoon until they begin to brown. Once browned, transfer chips to the preset rack using a slotted spoon, be sure to keep them in a single layer so they don't get soggy.
Sprinkle with sea salt as desired and cool completely.