I've made home-fried sweet potato chips a few times now and they are fab! I want to make a big batch for our Mothers Day party. How far in advance can I do the slicing and how do I store them in the meantime? The past couple times I've made them (in much smaller batches) I slice them, lay them out on paper towels for a while, then fry. Can I leave them on the paper towels for several hours without them turning brown? Anyone have any experience with this?