I made another soup this weekend to eat on throughout the week. A big pot of soup easily lasts us the entire week for lunches with a dinner or two thrown in. I don't mind eating the same thing for both lunch and dinner; if I do, I'll vary what I have with it (salad? bread? cooked greens?) so I don't get bored.
I realize that one reason I can just whip out a soup without a recipe is that I use the same "base" recipe for soups and just vary what I put in it, based on what's in my fridge/freezer. Since I figure some of my intrepid readers might like to experiment with making delicious, nutritious, and filling soups of their own (without much fuss!), I thought I'd post a short course on soup making.
I like to start my soups with a mirepoix, which is just a fancy way of saying onion, carrots, and celery. If I don't have celery or carrots, I simply start with onion, but I prefer celery and carrots for my soup base. Finely dice the mirepoix and saute in butter or a splash of olive oil until the vegetables begin to soften and get fragrant.
For those who are meat-eaters or like a little meat flavor in their soup, feel free to add a ham hock or bit of chopped stew meat, a smoked turkey leg (really good with split pea, incidentally), or something like a venison neck bone that is lurking in the depths of your freezer (yes, that would be us). Searing the meat helps release some of the flavors into the soup base.
The liquid part of the soup can be plain water, a bit of flavorful stock (you really should try to make your own occasionally, or at least buy good quality stock free of MSG or preservatives), or a bit of bouillon and water. We have a salt-free vegan vegetable bouillon that is nice to use if we don't have any vegetable stock on hand. (I use a salt-free bouillon because I can add my own salt, and I'm after the vegetable/herb flavor anyway. I'm planning on trying my hand at some homemade bouillon soon.)
Now here's the hard part: what are the main components of your soup? As a (mostly) vegetarian, I obviously want gobs of vegetables and beans. There is nothing wrong with a bit of meat or dairy, of course, for those who want something a bit heartier. I find the best soups showcase the vegetables and use the meat as a flavor rather than primary component. You can use a mixture of fresh vegetables or frozen, whatever you might have on hand.
The soup I made this weekend was a freezer clearing soup: I used frozen squash and a partial package of peas, a lone can of green beans I needed to get rid of, some beans we'd tossed in the freezer a while back, a frozen pepper, frozen leek tops leftover from another recipe, and some frozen celery. I also thawed out a couple of cups of pumpkin puree to add to the liquid, which was a delicious way to add flavor and thicken it a bit. My primary seasonings for this one were an Italian herb mix, parsley, nutritional yeast (which ups the umami quotient without using animal products!), and salt and pepper.
Other ideas would be to add more legumes (like lentils or split peas) for a legume-based soup, or adding more vegetables if you want a mixed vegetable soup. Potatoes, squash (winter or summer), greens, etc. make great soups. You could even roast cubes of vegetables to change the flavor profile. Adding milk, cream, or cheese (or a combination) would make the soup creamier and thicker. Adding a vegetable puree (like potato) would also thicken it up. Adding a bit of rice, oats, bulgar wheat, or any other grain lends a different texture to the soup.
Add your vegetables, legumes, and/or grains to the pot (after the liquid) and let cook until the vegetables are done and everything is tender. You'll want to taste and adjust your seasonings, since salt levels can vary wildly, depending. (And if you accidentally over-salt, just throw in a cubed chunk of potato to simmer until tender! Potatoes absorb salt like crazy.) If you plan to add cheese/dairy, wait until towards the end of the cooking time.
Making a good soup is largely a matter of taste, what you want in a soup, and (at least for me) which ingredients are available. I would just take the soup base and experiment with adding different ingredients and seasonings to see what you can come up with!