For when you want something better than the box at the grocery store.
Of all the ingredients in the kitchen, vegetable stock or broth is one that is generally unloved by the culinary world. You can't get the gelatinous goodness that's the mark of a great chicken stock from celery and carrots, and so much vegetable stock tastes like little more than very salty water. But I, like so many people, have loved ones who don't eat meat, or would rather not, and so no matter what reserves of great fresh chicken stock I have in my freezer, I so often find myself reaching for a box of ho-hum vegetable stock to use in soups, sauces, and giving grains some flavor. There has to be a better way to get simple, delicious vegetable stock.
So I set about trying to figure out the ingredients that would make a great stock that had no meat in it. Stock usually has bones involved, so this is more of a broth, but I use it like you would a stock—to give body and flavor to sauces, to act as the base of a soup, and to season however I want. I found that including celery and carrots gave the stock a vegetal flavor that I didn't love. Too much carrot makes the stock sweet, which isn't ideal for a jack-of-all-trades stock. I found I preferred the simple, umami-laced flavor of browned mushrooms, onions, garlic, and pepper.
I tend to leave salt out of stock when I'm making it so that it's more versatile as an ingredient—after all, you can always add salt later, but it's difficult to reduce it without also diluting the flavor you worked to get into the broth. But you can season it at your discretion and it will work perfectly well.
I also made this stock, as I now make almost every stock, in my Instant Pot because it takes about 45 minutes of pressure cooking versus several hours on the stove, and doesn't need to be babysat at all. You can, of course, adapt this to a slow-cooker or just a stock pot over the stove if you don't have an Instant Pot or would prefer not to use it. Use it in soup or stew or sauces, like this corn and mushroom risotto or this two bean soup.
Get the recipe for Instant Pot Vegetable Stock.