Not OP, but I would have thought a basic pantry included staples like rice, cheap dried beans, and pasta (probably elbows or shells, since they’re pretty versatile).
I’d also do mac & cheese, the same as theirs, but with different seasonings: a little sauteed, minced onion or a dash of onion powder; a tiny bit of mustard for creamier cheese sauce; and a dash of black pepper.
PS: This is great! I hope you do these regularly.
I’ve never had roasted barley outside of barley tea, so not sure if I’ll get the flavors right, but I’m thinking hearty salad. Roast a pan of bell pepper and kabocha (or similar squash) with a clove of garlic. Cook/drain a little toasted barley (not a ton, just a pleasant amount for texture/flavor) while that’s in the oven. Greens, roasted veg, cooked barley, conveniently leftover chicken, thin-sliced green onion, sprinkle of dried cranberries. Roast garlic goes in the vinaigrette.