I have a small planter on my balcony at the moment which is thriving with leaves, and in a few weeks I'll dig out the harvest to see what I got. People grow them in very poor soil, and even in literal bags of compost, or buckets. They're easy-going and almost trouble-free.
Growing chillis, tomatoes, or herbs on window-sills is kinda fun and rewarding, but growing a "proper crop" feels even more rewarding. And surprising because you have to wait until you dig things up to see how well you did!