I think I've mentioned before that the local markets will sell you one egg or a tomato if that's all you want or need.
The local delivery people are now offering the ingredients for one serving of various dishes. For example, you may fancy an avocado baked egg for lunch.
For 13.9元 / $1.79 USD (including 1元 / 14 cents delivery charge), they'll deliver you one avo and two eggs to the door. Recipe is included.
The only problem is there's a 20元 / $2.78 minimum charge so you have to order two or add something else. Maybe another dish for tomorrow breakfast.
Most of them have bottles of drinking water I'm sure they only stock to make up charges.
I'll mention some of the more interesting dishes and ingredients over the next few days.
There is the assumption that you'll have some staple pantry items - oil, soy sauce etc.