How to use the online timer
Thirty minutes of simmering, after the initial sauté of aromatics, is a reasonable guide for a soup built from already-tender ingredients like stock, tinned tomatoes, and quick-cooking vegetables. A soup built around raw dried beans or tougher cuts of meat needs considerably longer, sometimes hours, so this figure suits the quicker end of the soup spectrum rather than a long-simmered broth.
The point of that half hour isn't just to cook the ingredients through — it's to let the flavours actually combine. A soup tastes noticeably different, and usually better, at the thirty-minute mark than it does at ten, even if every ingredient in it was already technically edible from the start. A gentle simmer rather than a rolling boil keeps vegetables from breaking apart into mush over that time.
Taste and adjust seasoning right at the end rather than at the start, since salt levels shift as liquid reduces and flavours concentrate during simmering. If the soup's gone thicker than you'd like by the time it's done, a splash of stock or water loosens it back up without diluting the flavour too much.
Common questions
Why does my soup taste flat even though everything's cooked?
It probably hasn't simmered long enough for the flavours to combine. Give it closer to the full thirty minutes, and season right at the end rather than the start.
My soup went too thick — how do I fix it?
Stir in a splash of stock or water to loosen it back to the consistency you want, then taste again since diluting it slightly can also mellow the seasoning.