Some tips and tricks that I found helpful through experience, I hope you find them helpful too :)
Fruits and veggies:
Shop frequently for fresh items, it's easy to pop in the grocery store and pick up a what's fresh throughout the week.
Time your fruits depending on their lives, a hard avocado can last days in a fruit bowl, or longer in the fridge, papayas not so much so buy fruits in stages so you'll have the chance to eat a ripe fruit everyday until you take your next shopping trip. You don't want a whole bowl of ripe fruit on your hands the next day that you force yourself to eat then have to make another trip.
Fruits like pomegranate, oranges, apples last quite a while so eat those types of fruits towards the end of your week and the fresher fruits like berries, apricots, figs, grapes in the beginning of the week.
- Buy watermelon quarters
- Buy small melons, papayas or pinapples
Veggie tray, easier than buying so many veggies and having them lay around or forced to make something with them buy a:
- Veggie tray with broccoli, cauliflower, celery .. perfect stew/curry ingredients for a single meal. Leftover Tomatoes, cucumbers and fresh items can go in salad.
- Buy little packets of celery sticks rather than the whole celery which can go limp or bad if not used often.
- Buy potatoes and onions by the piece. Garlic and ginger too.
- Buy small gourmet cucumbers and baby carrots
- Buy baby bok choy instead of the large one
Fish and Meat:
- Buy fresh fish the day you plan to cook it from supermarket or fish market
- Frozen shrimps are good to have on hand in the freezer
- Canned tuna in oil comes in handy.
- Buy single serving plain yogurts if you need
- Buy small egg cartons
- Buy small milk containers/cartons/bottles.
If you have a cheese store in your city I highly recommend going there, it's not only convenient for buying in smaller portions but it's an experience all on it's own.
- Find cheesemonger and see what you can learn about cheese..
- French style bread baguetts are perfect, pitas can be frozen or refridgerated. Small toast loafs are great too and make bread pudding with leftover pieces of stale breads.
Easier to buy dried and soak overnight then boil, or buy tiny cans and coordinate foods in the week
Pasta: Buy dried and save in cupboard or buy fresh small package.
Grains: Couscous is a great starch to have on hand, easy to prepare and always comes in handy.
Rice (Basmati, and calarose) as well, I don't skimp on rice or buy it from a bulk store, I buy a good quality stuff. Borrow from parents/relatives the amount you need if you have to from time to time.
Baking supplies: If you don't bake a lot buy small bags of flour, brown sugar..etc. Buy yeast packets when you need them, and baking powders come in small containers. Make a homemade pancake mix that you can mix what you need when you crave it.
While a lot of recipes can't be halved or they turn out bad, at the same time a lot are pretty good, I've made small pancake batches as well as waffles, crepes and it always turns out good.
Condiments: A lot of them come in small jars, pickles, pestos and the like.
- buy olives by the weight from your supermarket or local gourmet store. Because this way you can also mix and match, and select a little of the varieties you like rather than just have a big jar of one kind.
Buy from bulk store: certain spices (not all, as they lose their taste and aroma and are useless), grains, cereals or items can be bought from the bulk store, cornmeals and bread crumbs for breading are good to have in small amounts as sometimes a package is too much or expensive.
A dollar store or ikea sales are great for tiny containers to store things instead of having bags of stuff everywhere or save store glass jars because they're perfect after running through the dishwasher and removing the paper labels.
The biggest secret for the solo chef/shopper is coordinating a weeks menu with a grocery list as not to waste ingredients, because shopping for "smaller" things unfortunately is more expensive and I'm all for savvy shopping but I hate wasting too.
If you think you can use up that whole head of cauliflower then by all meals pick it up and see what you can do with it... certain veggies and aromatics can be frozen for later use, like celery and leeks, a little prep in advance goes a long way, just be sure to store things in an organized fashion with proper labels so things don't get lost in the freezer.