Great question — answering as the UphillTech team:
These days many supermarkets sell 'ready to eat meals'*, salads and food that can be heated with just the simple kitchens that are available in almost all hostels. *These are often not cheap filling unhealthy options but very good meals, of restaurant quality. (Just a pan of water kept just under the boiling point with a sealed packet of food will be fine, and you can do that with just a kettle by refreshing the hot water.) Also you can do a lot with simple fresh food, little of which needs cooking, as long as you know how to do basic cooking. Cold cuts of meat, fresh vegetables, many kinds of bread and bread substitutes like wraps and ready made toast, ready to eat rice, pot noodles (often...
Full answer by Willeke: https://travel.stackexchange.com/a/85773 (CC BY-SA 3.0).
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