The Soup I Make When the Fridge Looks Empty
A flexible method built around onions, beans, and whatever needs using.

This is less a recipe than a sequence. It begins when the fridge contains several ingredients that appear unrelated and none that look like a complete meal.
Start with an onion or the nearest member of its family. Cook it gently in olive oil with salt until the sharp smell becomes sweet. Add garlic if available. A spoonful of tomato paste is useful because it supplies depth without requiring a full tin of tomatoes; let it darken against the bottom of the pot.
Next comes structure. A carrot, celery stalk, piece of fennel, or neglected pepper can be cut small and added. Uniformity is optional, but smaller pieces make the soup feel intentional.
Add stock or water, then beans or lentils. Tinned beans make the method nearly immediate. Dried red lentils dissolve and thicken the liquid. A piece of Parmesan rind contributes more than its appearance suggests.
The final additions should keep their identity. Greens need only enough heat to soften. Cooked grains can warm through without becoming paste. Lemon juice, vinegar, or grated hard cheese can correct a soup that tastes complete but dull.
The important step is tasting for salt after everything is together. Beans, stock, and cheese bring unpredictable amounts. Seasoning by habit is less reliable than seasoning the actual pot.
No version is definitive. The method succeeds when several leftovers become one coherent bowl and the fridge gains a little space.