For the pasta with tuna sauce, finely chop the onion and garlic cloves. Sauté the onion in a little oil, stir in the pinch of sugar and the tomato paste.
Add the can of pelati and a little water if needed. Cover and simmer gently for a few minutes. Stir in the tuna, then stir in the garlic and season everything with salt and pepper.
Finally add torn basil, mix with pasta as desired and serve.