Beans - obviously depends on the beans. I love just dumping a can of black beans (most of the liquid drained out) into a pot and add a ton of cumin and lime, then eat that with chips, sour cream, avocado, etc., and eat with tortilla chips.
If you have refried beans, you can do a seven-layer dip thing.
For garbanzo beans, this smashed chickpea salad is great (I like mine as a sandwich)
https://smittenkitchen.com/2009/01/smashed-chickpea-salad/
If you have white beans, you can make this white bean stew which is one of the best meals ever:
https://smittenkitchen.com/2011/01/chard-and-white-bean-stew/
For potatoes, you can do baked potatoes, a spanish tortilla, potato salad served with a roast chicken or something.