We all love the deep, rich flavour of caramelised onions, but let’s be honest: no one actually has the 45 to 60 minutes it takes to stand over a stove moving them around on a busy weeknight. Most recipes that claim you can caramelise onions in 15 minutes are lying. However, there is a legitimate kitchen hack that accelerates the process using basic chemistry.
Caramelisation and browning (the Maillard reaction) happen much faster in an alkaline environment. By slightly raising the pH level of your onions, you can break down their chemical structure rapidly, causing them to soften, release sugars, and brown in a fraction of the time.
The Quick Fix: Cut your onions and toss them into your pan with butter or oil as usual. Once they begin to soften (about 2–3 minutes in), add a tiny pinch of baking soda—no more than $\frac{1}{8}$ of a teaspoon per pound of onions. You will notice them turn yellow and soften almost instantly. Keep an eye on them, stir frequently, and you’ll have sweet, jammed, golden-brown onions in less than 20 minutes.