Tip 1 for having food on hand when you need to bug out...remember it has to be simple, not require enormous amounts of water or fuel to process or reconstitute and not be so heavy you can't carry it or stow it. That narrows it down some....forget the notion that you are going to actually live on a few grubs, worms and polluted water - unless you definitely have those skills and are caught in that situation. Othewise read on...
USCG/CCG and Department of Defense SOLAS Survival Rations come in a variety of flavors and sizes....made especially for temperature extremes and nutritional content as well as high "shelf life". No preparation is required. Boaters may recognize these from their on board survival kits.
Brands to buy are Mainstay, Datrex and Mayday and they come in 1200, 2400 and 3600 calorie sizes - SIMPLE. You can store these in your car all year and you can have 3 days worth on hand in a day pack with you when you travel. $4-$7 each.... a no brainer if you can afford them. High carb candy bars are a bad option...they will make you too thirsty - and fast.
Find these items discussed at length and for sale at CampingSurvival.com http://www.campingsurvival.com/emfoba.html
You are now going to ask about MRE's of course....if you've never had them and don't know how to use them....yes you need to familiarize yourself ahead of time.....experiments have shown folks with advanced degrees could not figure out how to use them....and if you can't function well...this may be a difficult task....they decay quicker in high heat so 5 years for SOLAS rations and 1-3 years for MRE's. When the military dropped pallets of them in Afghanistan no one knew what to do with them - but the boxes were so nice and sturdy they were used to build homes - out of food!
Hey, MRE's are great to have on hand in the car on trips and day hikes and if you can carry them on your hasty departure, all the better...just remember the mindset tenants below. Oh and also remember that some brands DO NOT come with heater packs (buy separately) so your food will be cold (safe to eat) unless you find a way to heat them up.....
Don't buy these surplus as they most likely were stored in high heat or are too old...actual military versions are not sold to the public...but you can get the almost identical thing from the same companies....also learn more about and purchase if you like at CampingSurvival.com http://www.campingsurvival.com/mreskits.html
Keep these dry and cool under 70 degrees and you can keep them for up to 10 years! We might talk about other less desirable bug out food options another time. Shelter in place food storage is a whole other animal....plenty of options and plenty of opinions......another time.