Peel the carrots and grate them finely. Put in a saucepan and heat until they release some juice. Cover and simmer briefly, then add the sugar and 5 tablespoons of water and continue cooking until the carrots are tender. Mix the starch with 10 tablespoons of water, add this to the carrots and simmer for another 5 minutes while stirring. Take the pot off the stove and let the carrots cool down lukewarm.
Cover a plate (approx. 20 x 30 cm) with foil, place the carrots on the foil and smooth out, then allow to cool completely. Then spread a thin layer of whipped cream on top and sprinkle walnuts on top. Roll up the carrots tightly with the help of the foil. If you like, you can also sprinkle nuts on the roll.