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Dry pasta
Chocolate - unsweetened, semi-sweet, chips, cocoa
Some basic spices (in small quantity) - Chili powder, cumin, cayenne, and the baking spices, cinnamon, nutmeg, ginger, mace. (Visit a site like Pendery's for some memory refreshing.)
Corn Meal
Dried fruits like craisins and apricots if you use them for baking or eating.
Any hot sauces you like (Pendery's is good for that too)
Coffee Beans
Tea

You'd be surprised what a stroll down the aisles in the supermarket can do for "reminders."

Also maybe-
Cornstarch
Powdered sugar
Vanilla
Canned/boxed stocks (if you use them)
Tomato paste
Any canned/jarred veggies like artichoke hearts, black olives, water chestnuts etc.

AND....
Mayo
Ketchup
Mustard
Pickles
Jam/Jelly
Evaporated Milk/Sweetened Condensed Milk/Dry Milk/Soy or Rice Milk?
Cocoa
Garbage Bags
Food storage bags
Saran Wrap
Cleaning & Dishwashing Supplies?
Lightbulbs?
Paper Products?
Snacks: Healthy or Sinful
Juices

What happened? My post didn't appear for a long time, so I tried to remember it and added a few items.

Items I can't live without:

Evaporated milk (not sweetened). Use it in coffee, to cream soups, in place of cream or half and half in so many recipes. Even after it's opened it has a long life in the fridge.

Nellie & Joe's Key West Lime Juice. Look for it next to the bottled lemon juice but know that it is a superior product. Very handy for pie, cocktails and anything that needs some zip. Great to have on hand if you want to make a lime vinaigrette or something Thai or some guacamole and don't have a fresh lime on hand.

Lawry's Seasoned Salt. No other brand. Some purists may scoff, but it is one of the best things to have especially for traditional potato and macaroni salads, deviled eggs, many types of soup and for seasoning breading for fried fish or chicken. Once you start using it, you will not want to be without it.

^^^cmtigger is right. Figure out what you cook most. If you don't bake or if you bake alot or if you like to cook Thai or Italian, you'll need different things sooner rather than later.

I tend to stock the pantry when things I use go on sale. No sense in going out and paying full price on items to fill your pantry that you might not use.

Like during football season, the Red Gold Tomato products go on sale.
I buy the limit and stock my pantry so I'll have canned tomatoes for a while. Bc I know I'm going to make chilli or red sauce or soup.

When we moved I kinda went bezerk and tossed or gave to friends and family all the pantry stuff bc I didn't want all that sitting in storage and god knows what might get into it.. So we had to start all over, too. We didn't do it in one day. We've been in our new home for about 9 months and our pantry evolved over that time and now, it reflects our tastes and what we cook.

As for the spice cabinet, that too will evolve. I have a lot of Asian seasonings and a lot of chillis bc I love Asian cuisines and I also love to make chilli (not together).

Sriracha! Please people don't ever cook for me. :-)