What do you need:

It is always a good idea to have a store of food in the home "in case of emergency" but what is it best to store.

A good start is to work on a shorter period, say three weeks, then you can multiply by four for three months supply...

This list is of course aimed at the UK, other countries will need to source the items locally.

Rice and Pasta

Rosti. Available from most large supermarkets. Comes in a foil pouch and lasts a couple of years. Basically grated potato and sometimes onion / bacon etc. Lasts a good couple of years with no refrigeration. Nice as part of the Sunday fry up anyway.

Instant Mash. Not great on its own but now available with onion of cheese. Okay for topping off tinned mince as a cottage pie, frying with tinned veg as bubble and squeak.

Savoury biscuits. I like the hovis ones but Ritz, or cream crackers etc. are fine. Can be combined with spreads of choice. Get the ones in metal tins if possible

Ground cornmeal (Tesco finest). Makes great Tortillas and lasts for years.

Packet tortillas and Naan bread lasts a few months - if you use them anyway, stock up.

Tinned new potatoes - boil em, fry em even mash or roast. Dirt cheap from Aldi or Lidl

Fruit & Veg
Dried onions and dried garlic are a must for me. They liven up the dullest meals. Dried onion steeped in hot water for a bit and fried makes tinned hot dogs good.

Dried Beans - kidney, haricot, butter - whatever you like - always good and last (literally) for years

Never forget the humble sun dried tomato but also dried chillies, mushrooms and all dried veg - again - lasts for years

Tinned beans - not just baked beans but also kidney beans, Haricots etc (good for chillis)

Tinned peas (mushy or ordinary - your choice). Dried peas last a long time too.

Lentils, pulses and chick peas - great for soups and stews. You can mixed packs of "soup mix".

Dried fruit is great - I love apricots and apple rings but go with what you like. Beware added sugar for day to day but thats fine for emergencies. Try health food shops. Dont forget brazil nuts etc. too.

Tinned fruit such as peaches, pears and fruit salad can be eaten cold. Pie fillings are nice hot with custard

Christmas puddings last a good 2 years and can be steamed easily on a fire

Tinned puddings (Heinz do some nice ones like spotted dick and stick toffee) last for ages and are nice for a cold day

Meat / Protein
Corned beef (combine with mash and dried onion for hash)

Hot dog sausages. Nice to eat anyway. wrap in tinfoil and a couple of sheets of the Telegraph. Burn the newspaper. Hot meal!

Bacon Grill - slice thin and grill or fry - a great standby. Goes well with Rosti.

Lidl do tinned peanuts. 2 year shelf life - great stuff - nice for a snack day to day as well (also Cashews etc.)

Tinned fish are great especially tuna and sardines, but don't overlook kippers, tinned crab etc. if you like and will eat them

Lidl do a dairylea type cheese triangle jobby that does not need refrigeration. Lasts 2 years. Nice beaten into mashed spuds etc. or spread on ritz crackers etc.

Peanut butter is a great source of fat and nice on biscuits. combine with chilli for a satay sauce

Dried milk (Marvel, 5 pints etc.). Useful for home baking and as a standby.

UHT Milk - don't like it and bulky but a couple of bottles are handy.

Keep a couple of spare bottles of olive oil. Useful as a butter substitute for breadmaking etc. and all the normal uses

Instant custard - whats not to like?

Don't forget spices - chilli, curry powder etc. can make a bland meal nice

Dried egg. Goes well will Rosti and Bacon Grill. Try Weigh and Save but they have to order it. Larger Tescos sometimes.

Honey. Sugar substitute that NEVER goes off (they found some in the pyramids that was edible).

Baking Powder. Useful for making bannock etc. as a bread replacement (the guys have eaten my bannock - it also makes great pancakes too)

Flour - plain white and strong bread flour. Do you have baking facilities? If so add some yeast.

Salt and pepper - a large jar of each cost pennies and is useful in bread making (salt) and livening bland food (pepper).

Sauces - a spare bottle of your favorite (tomato, brown etc.)

Jams and spreads last for ages (years) and are handy on biscuits, puddings, bannock etc.

Also go for curry sauce, pasta sauce - all the ready made jar stuff - will liven up bland ingredients

Also, have some spare Bisto. Don't overlook packet and jar sauce powders - white sauce, onion , parsley even chip shop curry will cheer up basic carbs and make em palatable

Ready Meals
Always handy stuff for a long day anyway. Heres a few to consider

Beans and Sausage / Full Monty etc.

Tinned Soups (especially "Big Soups"). Packet soups are handy too and only need hot water

Tinned Chilli and Curry

Ravioli and Spag Bol in tins

Fray Bentos Pies and meat puddings in tins can be cooked in an improvised oven or some can be steamed / boiled.