Some great additions already suggested (love the list by Jericoshost and the options outlined by jimbob), maybe I’d be thinking of a few new items but also ways to make the most of the resources available.
Get those big bags of oats already proposed by KA101 and add some cartons of UHT milk as well as the powdered stuff (why is all milk in C:DDA fresh and in glass bottles to rot before you can get to it?- surely some people have a stock of long-life milk that doesn’t need to be stored in a fridge) - this in conjunction with all the berries, apples and even honey comb etc. that are all in the environment means you could get a half-dozen porridge recipes that are very filling and give a nice morale/health boost. Same could be said for the drier granola/energy bar possibilities as mentioned by Fengfirth, if you were to have recipes for them rather than just available as loot, they’d need more honey and maybe the addition of some bags of nuts (which would make for a fairly healthy snack in itself)?
On the fruit line, we’ve already got pies and the ability to can/vacuum pack apple slices, so why not add preserves for the berries you collect in the wild and the occasional citrus - they could need 3 sugar and 5 total fruit, put 'em in a normal glass jar but they hold 10 portions or so of Strawberry, Blueberry & Mixed Berry jams, Marmalade and Lemon Preserve; add 'em to your porridge, make a sandwich or enable the ability to toast bread and spread 'em… You could add grapes to the fruit and peanuts to the collection of nuts available to get you some Grape Jelly & Peanut Butter too!
Love some of the other ideas mentioned - we really need a more generic big bag of pasta to go with those grains & rice - get the pasta baking with those underutilised tins of tuna and corn, also rabbit with wild vegetables and mushroom risotto anyone?
I’d like to see a few more additions - extra tinned fruits & veg, stews & casseroles; all those packet food varieties (noodles/cup-a-soups etc.) that just need hot water, some type of cookies or biscuits for when you can sit down with a cup of tea/coffee would be nice too - even better if we’ve got the hot chocolate going on. Final thing I can think of is some sort of cheese segment in waxed paper and smoked cheese in plastic along with a variety of crackers - they’d also go great with the grapes not turned to jelly and a scavenged bottle of jimbob’s wine! You might even drop-on lucky and find a full cheese wheel with 16 portions…
Hope some of that is useful and maybe even gets implemented - the last thing I suggested to add to C:DDA was the public works building and that kinda turned out O.K.
P.S. - please forgive my rambling stream-of-conciousness writing style.