Heat oil in a large heavy saucepan; add onion; saute over low heat, stirring, until tender and golden, about 5 min. Add the garlic; saute 1 min. Meanwhile, brown the ground beef in a skillet, stirring to crumble meat; drain off fat; add to the onion mixture. Add the tomatoes, tomato sauce, 1 tomato sauce can filled with water, the tomato paste, parsley, 1 tsp salt, the basil, oregano, pepper, and bay leaf. Heat over medium-low heat to simmering. Simmer, uncovered, over low heat, stirring occasionally until sauce is thickened and flavorful, about 1 hour and 15 minutes.