Q: How do I make tasty soups fast?A: The simplest way I know of is to invest in a pressure cooker.
A pressure cooker works by increasing vapor pressure on the surface of liquid, which in turn raises its boiling point, allowing it to cook hotter. The hotter your soup cooks, the faster flavors extract and recombine. In my testing, I've found that a basic chicken soup that takes 2 hours to simmer on the stove packs in as much flavor with just half an hour of pressure cooking. Similarly, pureed vegetable soups come together in about a third of the time.
There are other tricks to making quick soups as tasty as their slow-simmered counterparts. One of the main flavors that develops as you make a meat-based broth is umami, or savoriness. It's triggered by an organic compound called glutamic acid. By adding concentrated forms of glutamic acid as you cook—a small splash of soy sauce or Asian fish sauce, a teaspoon of Marmite, or a Parmesan rind—you make meaty soups taste meatier.
And for that full mouthfeel of homemade stock, there's no shame in using gelatin. Bloom a packet of gelatin in a quarter cup of stock for each quart of soup, stir it in, and simmer: rich broth in a fraction of the time.
Finally, a tip for pureed vegetable soups: Instead of straight-up stock, I use a mixture of stock and bottled vegetable juice (use carrot juice for a carrot soup, spinach juice for a green vegetable soup, etc.). I cook the veggies in that mixture, and then when I transfer it to the blender, I add a splash of fresh vegetable juice. The combination of cooked and raw veggie juice adds tons of complexity with minimal effort.
Kenji Lopez-Alt is the chief creative officer of Serious Eats (seriouseats.com), where he writes The Food Lab, unraveling the science of home cooking.