Note: This is a very old recipe and it is impossible to tell you how much sugar to use. It depends on the size of your potato! I made this today and I am posting pictures below to try and help you. I only had a potato that was 5 inches in length. This is too big. I cut it in half. Also, today I baked the potato in the microwave because I thought it might take less sugar that way. It did not take any less sugar by baking. I used about 5 cups of powdered sugar. Peel the potato, mash it, and start adding the sugar. When you get it stiff enough to turn out on a dough board, use sugar on the board like you would flour if you were making dough. Also sugar your rolling pin. Keep working sugar into the mixture until you can roll it out. Once you roll it out, spread with enough peanut butter to cover it, roll it up and cut in pieces. If you have trouble getting it to roll up, run a knife along the edge and add sugar. I keep this in the refrigerator. Click to follow The Southern Lady Cooks on Facebook.