Pre-packaged emergency meals are convenient, but if I use them too often I  get sick of the same ones over and over again.  Regular grocery stores are actually full of stuff that works just fine for backpacking.  Some of the instant food at grocery stores even has recipes on the back that can be easily modified  (i.e. dried tomatoes instead of fresh, powdered milk, and so on).  

Powdered Milk (look for Nido in the Mexican food aisle)
CousCous (Moroccan style)
Dried Fruit
Nuts
Tuna pouches
Peanut butter in a plastic jar
Mylar bag of wine
Instant oatmeal or granola
Starbucks Via coffee
Lipton cup of soup
Knorr Pasta sides or soup mix
Hungry Jack hash browns
Idahoan mashed potatoes
Seaweed snacks
Peperoni or other dry sausage
Rice noodles
Pesto mix
Cucumbers, snap peas (for the first couple of days)
Parmesan cheese
Powdered eggs
Walker's Shortbread
Dried mushrooms
Humus mix
Near East Pilaf/rice/quinoa mixes
Tasty Bites Indian meals
etc...

You can use this stuff to construct basically  edible meals.  For instance,

Breakfast-- Granola with dried fruit and nuts in Nido, Via coffee with more Nido
Lunch -- Crackers, tuna pouch, dried seaweed snacks, granola bar
Dinner-- Near East pilaf with dried mushrooms, Walker's shortbread, mint or ginger tea






Idahoan mashed potatoes