When I'm cutting, on most days I make a pan of cod + egg whites. I stock my freezer with one pound packs of frozen Alaska cod from Trader Joe's.
One pound of cod is roughly 350 calories and 80 grams of protein. I start that in the pan first with a little olive oil and add one cup of egg whites which is 125 calories and 25 grams of protein. Scramble it up for a few minutes and serve.
That's a tasty meal low in calories and super high in protein. I break it into 2 or 3 different meals throughout the day, and I know I have 500 calories and a lot of my protein requirements covered. The rest of my calories are a balance of fat and carbs, and it's easy to stay within my fat loss range eating this way.
This could also be a muscle building meal, but I'd sub in some whole eggs instead of the whites. Cod is awesome. The Rock eats about 600 pounds of it per year and he doesn't look too bad.