For years, I’ve written about the merits of homemade stock (or at least stock made by a real person), even insisting that if it’s a choice between canned or boxed stocks and water, you’re better off with water. At their best, the canned and boxed versions taste like salt; at their worst, like chemicals.

But here’s the problem with homemade stock: It’s so good that it doesn’t last long. What’s needed is something you can produce more or less on the spot. Although water is a suitable proxy in small quantities, when it comes to making the bubbling, chest-warming soups that we rely on this time of year, water needs some help.

Fortunately, there are almost certainly flavorful ingredients sitting in your fridge or pantry that can transform water into a good stock in a matter of minutes. The process may be as simple as simmering in water fresh herbs, mushrooms or even tea, or browning aromatics to create richness, or adding staples like crushed tomatoes or coconut milk. To further maximize flavor in minimal time, it pays to reach for ingredients that pack a punch, like miso, anchovies, chipotles, Parmesan rinds, sometimes even leftovers.

These recipes are meant to be fast, so by ‘‘simmer,’’ I mean as little as five minutes and no more than 15. You can season these stocks at the end with salt and pepper to taste, or wait until you’re ready to turn them into full-fledged soups. In the continuing spirit of speed, convert these into soups using things that also cook quickly: some combination of chopped greens or other tender vegetables, cooked grains or beans, shellfish or thinly sliced meats. The recipes here yield about six cups of stock, enough for four servings of soup.

I tend to make these sorts of on-the-fly stocks in small, one-time-use batches, but if you want or need to store them, you can do so in the freezer for weeks or months, or in the fridge for a few days. Whether you stock up or not, take comfort in knowing that soup is never more than a few minutes away.