I like to make my own home miso soup, but add things to it. So you need to get a container of soy paste, then mix it with boiling water as per the instructions on the lid, then add diced firm tofu(!), some thinly sliced green onions, baby mushrooms of any kind (I recommend enoki), and some bok choi if you're me and you love bok choi. You can toss anything else you have lying around the house in there: dulse or other bits of seaweed are good for nutritional value, but not everyone has it in their cupboard.

Experiment! But really, the tub of soy paste is invaluable to have around, and will last for aeons. You can buy it in the "exotic food aisle" across from the meat section in the College Park Dominion if you're looking. They have dulse there too, as I recall.