For backpacking, this seems to work for me:

Breakfast: Quaker instant oatmeal & Mountain House eggs ... plus you can't forget the Starbucks Via instant coffee!

Lunch: Snack sized flavored tuna & crackers or bagel

Dinner: Mountain House (or equivalent) entree (Note: In my opinion, many of the 2 serving bags are good for one person ... I've often found a full bag only contains five or six hundred calories)

Good snack foods include bars (I like LÄRABARs best now), trail mix and beef jerky.

One note about the Mountain House eggs ... I really have to find a something better for protein in the morning. While I enjoy scrambled eggs & oatmeal as a meal, re-hydrated eggs are only vaguely egg-like smile. I'm thinking at a minimum I need to break down and buy a small fry pan and some powdered eggs; as you can tell by my food list above, I really just boil water now - I don't cook.

Also, for anyone interested in making their own backpacking food, I'd check out BackpackingChef.com. While I haven't tried any of the recipes my self yet, he seems to have some really good ideas for home-made backpacking food.
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Victory awaits him who has everything in order — luck, people call it. Defeat is certain for him who has neglected to take the necessary precautions in time; this is called bad luck. Roald Amundsen