If the potatoes are not rotten, but just "soft", simply peel and soak in a bowl of water overnight. Cut them for hash browns or french fries. Let them soak for another 10-15 minutes. Remove potatoes from water and cook. Use the water on your plants.
I make stuffed potatos and crash potatos of them, no pre soaking necissary. microwave them, mash and add necissary ingrediants. love those crash potatos! for crash potatos I mic. them, mash them, then add olive oil, salt free butter, garlic and parmesian or other shredded cheese, and toast them in the toaster. depends on what's on hand and what we want for stuffed potatos. use your imagination.