1. Heat the olive oil in a pot and add the onion and garlic.
2. Saute, stirring regularly for about 3-4 minutes.
3. Liquefy the tomatoes with a blender and add them in the pot.
4. Add the salt and bay leaves.
5. Cook over low temperature for 45 min. (or until the desired thickness is achieved), stirring regularly.
6. Add the sugar, chopped basil and butter 10 min. before the sauce is ready.
7. Boil the penne, strain and toss with some of the pomodoro sauce.
8. The remaining sauce can be kept for 7-8 days in refrigerator or to be frozen.
9. Serve with freshly grated or shaved Parmesan cheese on top.
10. Garnish the Penne Pomodoro with fresh basil.