1. Peel and chop potato into 1 inch (2.5 cm) pieces. Place in a large microwave-safe bowl and cover with plastic wrap. Microwave on high in 2 minute increments until soft and easily pierced with a fork, about 6 minutes (use caution when removing plastic wrap – the steam will be extremely hot).
2. Once soft, use a fork or potato masher to mash the potato until smooth.
3. Start adding Redpath® Icing Sugar to the mashed potato, 1 cup (120 g) at a time, stirring well with a wooden spoon after each addition. The mixture will be quite thin and watery at first, but will begin to thicken after the first 2 cups of Redpath ® Icing Sugar are added. Continue adding Redpath® Icing Sugar as needed until mixture becomes a stiff, kneadable dough.
4. Wrap dough tightly in plastic wrap and chill for 1 hour.
5. Sprinkle a large sheet of parchment or wax paper with Redpath® Icing Sugar. Place chilled dough in centre and sprinkle with more Redpath® Icing Sugar. Cover with a second sheet of paper and roll into a rectangle about 16 x 10 inches (40.5 x 25.5 cm). If the dough cracks a bit when rolling, use your hands to gently press it back together.
6. Spread dough with the peanut butter, leaving 1 inch (2.5 cm) of a long side uncovered; sprinkle peanut butter with peanuts, chocolate chips and salt. Moisten the uncovered 1 inch (2.5 cm) of dough with a bit of water and starting on the opposite end, begin rolling up the dough into a spiral. Press moistened end of dough firmly to seal and wrap spiral tightly in plastic wrap; chill for 1 hour.
7. Once chilled, slice the roll into ⅜ inch (1 cm) slices and serve. Nutty potato candy will keep in the refrigerator in an airtight container for up to 1 month.