I'm normally adverse to junk but recently I developed a taste for chocolate muffins and coco pops never having eaten either in my life, I only noticed this week that a horrible scalp problem I've had for the last couple of years has suddenly cleared up. I don't know if they're related but I did wonder..... I'd buy them for a food bank too, muffins are very filling and coco pops are delicious. I've even given them to my dd and she hasn't exploded or anything. I think that comfort foods are nice to have, more so for people who are so miserably poor that they have to use food banks.
Basics that are easy to make a meal from and use little electricity are probably best; bread, milk, butter, cheese, eggs, potatoes, tomatoes, carrots, chicken, tinned peas, beans, apples, pasta. Most people will eat those foods, most wouldn't have a clue what to do with quinoa, many veg are unappealing on their own and if you don't know how to cook them. Everybody can make toast or put a sandwich together, most can boil some pasta/potatoes/eggs, I think simple foods that everyone will recognise, know how to prepare and want to eat are the best.
I'd also put in tea bags, coffee and biscuits. It's the little things like having a neighbour over for a cup of tea that can help alleviate the misery and isolation of poverty.