Drain the tuna. Wash the cherry tomatoes and cut them in half. Wash the basil leaves, pluck them and cut them into small pieces.
Then put all ingredients, except for the basil leaves, in a high pan or a correspondingly large saucepan and bring to the boil with the lid closed. The basil stalks are also cooked.
Simmer over medium heat for about 10-12 minutes. Stir regularly so that nothing burns. If the liquid has boiled off but the pasta is not yet done, add a little water and let it simmer again. As before, don`t forget to stir.
When the pasta is done, remove the basil stalks and season the pasta. Fold in half of the basil leaves, use the remaining leaves to garnish.