Store what you eat and rotate the stock
Eat 10 cans of soup- pull 10 in from the garage. Buy 10 more for the garage.
Keep a sharpie in the garage to date when you purchased the items
Yep, this is what we do. Buy food that we actually eat and rotate our stock.
Every can that goes in the pantry we find the date code and write the date in big black numbers on top of the can where it's obvious.
The other thing I do is enter everything into a spreadsheet. All foods that go in or out of the pantry get added or subtracted from the sheet.
Item description, can size or weight, expiration date, and pantry location all go in the spreadsheet.
That makes it easy to see what we have in stock, and also I can sort the items by the expiration date so it's easy to see which things need to be eaten soon and plan meals to consume them.
Looking at my pantry list I see I have a jar of tomato & basil marinara sauce and a jar of peanut butter that expire this month so I'll make it a point to make pasta soon or something to use up that sauce and maybe I'll make a batch peanut butter cookies.
And I'll add those items to my shopping list to get a few fresh jars for the pantry.