Add the olive oil and garlic to a sauce pot, and cook over medium heat for 1-2 minutes, until the garlic is soft and fragrant.
Add the tomato sauce (or crushed tomatoes), tomato paste, sugar, salt, basil, oregano, and pepper. Stir to combine.
Cover the pot (leave the cover slightly askew) and allow the sauce to come to a simmer. Reduce the heat to low, and let simmer for 15-30 minutes.
Be sure to taste the sauce as you are making it- add more (or less) spices, salt, etc to your taste.