What do you always have on hand? Why?
I’d count refrigerated items as pantry staples if they keep for longer than a couple weeks.
One recent addition to my pantry has been dried chillies - great base for red chile sauce for enchiladas. Those plus maseca and some beans (also both staples) and I have a base for amazing enchiladas or tacos or whatever.
A pantry’s personal. It should have the ingredients and spices you frequently cook with. For some folks that’ll be pasta, other folks that’ll be rice. You know your pantry’s set when you could make a satisfying meal with one or two fresh ingredients.
A well stocked pantry is one where none of your usually ingredients is empty or running low.