We had this with pasta, I guess it could go with other things too though. I'm getting quite into making pasta sauces from scratch rather than using a jar. This is because I realised that pasta used to be one of my favourite foods, whereas now it just seems like a make-do meal if there's nothing else to hand. So this is me reclaiming my pasta!
Take one tin of haricot, cannelini or blackeyed beans, tip into a roasting tin.
Squash three or four cloves of garlic and scatter the bits around the roasting tin. Splash the whole lot with olive oil. Put the tin and its contents in the oven on 200C for 20 minutes or so.
Chop a couple of handfuls of green beans and an onion (I usually use red ones) and cook in olive oil for about 10 mins at medium heat. (Olive oil can go yucky at higher temperatures, although NOT poisonous as some have claimed) Add the contents of the roasting tin. Add a tablespoon or two of tomato paste (your mileage may vary on this one) then enough hot water to cover everything. Bring to the boil then simmer for about half an hour. Add more water if necessary.
Because I've recently become a fan of aioli, I added some vegan mayo - maybe two tablespoons - during the last five minutes before serving. I think this improved the texture and taste a bit, but it is a completely optional part of the recipe!