1. Cook the spaghetti, refresh with cold water and leave the pasta to cool. Stretch out some plastic foil on a chopping board and line up each individual spaghetti side by side.
2. Cut both ends of the pasta so that it's straight — you should now have a spaghetti rectangle in front of you.
3. Mix the ricotta with the tomato sauce and grated parmesan.
4. Now place the spaghetti rectangle with the foil on a sushi mat. Spread about 3 tbsp of the ricotta mixture on the left third of the pasta (leave a small margin free) and place 5 cooked meatballs on top of the mixture.
5. Next, use the sushi mat to roll everything up. Remove the foil, leave the roll to cool and then cut it into 5 equally-sized pieces.
6. Garnish the Spaghetti Sushi with tomato sauce, grated parmesan and fresh basil.