Saute onion in olive oil over medium heat for 5 minutes. Add garlic and oregano, salt & pepper. Saute an additional 2 minutes.
Add tomatoes, stock, herbs and season. Bring up to a simmer. Cover and let simmer for 20 minutes.
Stir, then add the milk. Taste, re-season and serve with shaved parmesan and fresh basil on top.
Since we all agree that grilled cheese sandwiches and tomato soup should not be separated, that is my serving suggestion. My only recommendation is to seek out a whole grain bread that has no preservatives, additives or other yucky oils or sugars.
I love Ezekiel bread. Also, my local health food store offers whole grain lavash rounds. I toast them with olive oil and sprinkle cheddar cheese on top. Slice into triangles and these are an excellent alternative to the traditional grilled cheese sandwich!