Pantry, two freezers. Shop the local stores for the 'loss leaders', and stock up on them. They tend to rotate, especially around holidays. Use coupons, but make sure it is a bargain. Expensive canned goods with a slight coupon discount may be more expensive than store brands of equal or very close quality that are not even on sale. Avoid already prepared food and instead concentrate on 'makin's '.
Don't buy quantities or items that will go bad in the fridge--it isn't ever a bargain if you end up throwing it out.
Buy in portions you will consume unless you like leftovers, and if you have leftovers, have a leftover night every week, be creative with them, that bit of roast may star in the stroganoff. It's amazing what does well in soup.
When it comes to canned goods (which store well between sales), often the store brands are as good or better than the name brands. We did a taste test with things like canned tuna, beans, and other staples, and found what we liked.
Have a little of everything you'd like to eat, but note what you use the most of and load up when it is on sale. Buy by the case, even if there are only two of you, rotate your stock, and when it starts getting low, watch for the next sale.
Can your own if you can get good deals on produce in season or grow your own. (lots of info on the web)
Fresh produce is bloody expensive, and doesn't store well unless you can it.
Meat often goes on sale around barbecue holidays, that's a good time to stock up, freeze it with a seal a meal (eliminate air), and it will keep a long time in a good deep freeze. Grains like rice can be sealed up the same way, bought up in bulk, but put oxygen absorbers in the bag before you seal it to help it keep, and then store it some place cool.
There is a lot you can do. If you have the patience to cook dry beans, those are commonly cheaper in bulk, too.
We also use a dehydrator to dry garden produce that makes good powdered or ground additions to soup or stew, or as seasoning. Some of last year's habaneros are now still a green powder, and downright dangerous if over used.

You can eat well, even if not fancy, and do so fairly cheaply if you take the time.