Heat the oil in a non stick pan on medium heat, when hot, add the garlic, stir for 30 seconds or until the garlic is fragrant.
Pour in the chopped tomatoes and stir together. Stir in the oregano and season to taste with salt and pepper as desired. Reduce heat to low.
Add the drained tuna, break that up a bit and stir into the tomatoes, let simmer for about 15 minutes, stirring occasionally.
While the sauce is simmering, heat a pot of salted water to a boil, then add the pasta of your choice, spaghetti or fettuccine would be perfect. Cool until tender, drain. For the pasta, figure about 160-180 grams (6-7 ounces) for 2 servings.
After 15 minutes of simmering the sauce, stir in the drained capers and simmer for another 5 minutes.
Divide the pasta between two plates, spoon on the sauce, top with grated Parmesan, enjoy.