While toying with the idea of going vegetarian (to see if it would affect energy levels), and just reducing intake of red meat as whole I have started using lentils in a lot of meals, especially in dhal and potato curries.

Seriously easiest and nicest meal possible. http://www.vegsoc.org.nz/recipe_070307.html For a quick dhal recipe. Quick to zap reheat and easy to eat in a mug at the desk.