I'm planning on buying food from markets during my trip to save on $$, and I'm wondering about what sorts of "backpacker's cuisine" exist out there. Is there anything more exciting than bread and nutella? Is it a good idea to bring containers to store food?
There's tons of stuff you can get! We tried to make sure the hostels that we stayed at had a kitchen that we could cook things in. We boiled pasta, made salads, stir-fry, rice and had a bunch of stuff that we would eat normally at home. If you're going to eat on the go, you can make cheese sandwiches, have yogurt and mix it with trail mix (either bring yuor own because it keeps for a while, or buy some at the supermarket), eat fresh fruits nad veggies, etc. We also found a lot of pre-made sandwiches and veggies with dip at grocery stores. They were a teensy but more pricey than making them yourself, but a lot cheaper than going out to eat. Another thing to suggest is look for cheap restos. When we were in Spain, we ate tappas all the time - they were very cheap and filling!
I would recommend to bring a small tupperware in case you have leftovers and want to eat it the next day (make sure they keep well in a fridge before you go out) and some plastic utensils.
Just as a side bar, I'd recommend to bring some vitamins with you in case you don't get enough nutritious stuff in your food. Vitamin C was a lifesaver!
Consider going to places that have "all you can eat" deals. Then stuff some tasty treats into your bag for tomorrow's lunch!
I agree with the mtlchica about taking vitamins - a great idea.