When it goes wrong · Sweat
They are still crunchy after ten minutes.
Can you save it?
Reviewed for this symptom
Raise the heat a little, add a pinch of salt to draw water out, and cover for a few minutes — they will soften. If the pan is overfull, split it in two.
How to confirm the diagnosis
Observable cues, not inferred user state
- No sizzle at all
- The onions are still opaque white
- The pan is piled high
Not this?
- The onions browned.
- The finished sauce has a raw vegetal edge.
- Everything caught and burnt at the edges.
What actually happened
Only this symptom
Heat too low, or too many in the pan. Sweating is gentle, not cold — it should be actively cooking.
The full mechanism
Shared by every sweat failure
Sweating and sautéing use the same pan and differ only in temperature and intent. Below browning temperature, an onion's cell walls break down and it releases water and turns translucent; its harsh sulphur compounds volatilise off and its sugars stay unbrowned, so what you get is sweetness and depth without any roasted note. That distinction matters because browned onion tastes of browned onion — assertive and slightly bitter — and there are dishes where that would dominate everything else. A béchamel, a risotto base, a pale soup all want the aromatic foundation and none of the colour. The released moisture is also doing work: it keeps the pan temperature at or below 100°C on its own, which is why a lid or a pinch of salt makes sweating more reliable than watching the heat.
The full Sweat lesson — how to tell, where to practise it, what it carries to.
Next time
Prevent this specific failure
Sweat over a gentle but active heat, salted early, in a pan that is not overloaded.
What right looks like
Shared by every sweat failure
- Onions go from opaque white to translucent with no gold at the edges — that transition is the entire endpoint.
- There is a gentle, wet sizzle rather than a hard one, and visible moisture in the pan.
- They smell sweet and mild rather than sharp, which means the volatile sulphur compounds have gone.
- A piece squashes against the side of the pan with no resistance.