Out of curiosity, I'm wondering if there's a meal you could put together that encompasses everything you need to be healthy for 600 calories or less per meal.
In the same vein as those crazy mono diets but instead of doing something stupid like eating only bananas for weeks on end, you have a balanced healthy meal that's precooked. You could eat the same meal, all day every day and lose weight without worrying about making a bad choice because you already made the choice.
What's a meal that tastes good and accomplishes this?