Mirepoix is the least glamorous idea in cooking and the one that quietly holds up half of it. Two parts onion, one part carrot, one part celery — cut large for a long simmer, cut small for a quick one. Once that ratio is in your hands you stop needing a recipe for soup at all.

Cut the vegetables in big chunks for stock. A three-hour simmer will extract everything from a two-inch piece of carrot, while a fine dice breaks down into sediment and clouds the pot. The same rule governs the heat: a bare simmer with barely a bubble breaking the surface, never a rolling boil, which emulsifies fat into the liquid and turns it opaque.

The last step is the one people skip. Pour it off through a fine sieve, resist the urge to press the solids, and cool it uncovered before it goes into the refrigerator. What you get is a clear golden stock good enough to drink, and you will genuinely stop buying it in cartons.