Caramelised onions gain extra richness and a silkier texture when a chef's favourite fridge staple is added not just at the start of cooking but again right before serving, according to Chef Lindsey Farr.
Butter is essential for caramelised onions because it "adds richness and flavour", said Lindsey, who noted that the dairy ingredient is "where a lot of the depth comes from". She advised: "Finish with an extra knob of butter right before serving for a silkier texture."
Why butter beats oil
Because butter contains milk solids, it kick-starts the browning process far more quickly than vegetable oils and coats the onions with a more appealing glaze. It is also considerably more flavoursome than most neutral oils such as vegetable, olive, rapeseed, and sunflower oil.
Choosing the right onions
Red onions, yellow onions, white onions, shallots, and extra-sweet varieties are all excellent choices, each producing slightly different results, some sweeter and some more bitter. More often than not, the best outcome comes from combining a variety of different onions, though this is by no means essential.
Red onions boast a deeper, richer flavour with a slightly bitter edge and less sweetness. Yellow onions, by contrast, offer a bright, vibrant taste, very mild bitterness, and a pleasant sweetness to round things off. Shallots strike a wonderful balance of sweetness, combining both bright and deep, rich flavours with just a touch of bitterness.
How to make caramelised onions tastier
Ingredients:
- One quarter cup of unsalted butter
- One tablespoon of olive oil
- 900g of onions, cut in half lengthwise and sliced a quarter-inch thick
- One teaspoon of sugar
- Sea salt, to taste
- Black pepper, to taste
Method:
Begin by melting the butter and olive oil together in a large pan over a medium-high heat. This should take around one to two minutes and will appear glossy and smooth.
Add the onions and stir to coat them evenly. Spread them out into a single layer to ensure they cook consistently throughout. Sprinkle with sugar, which helps kick-start the caramelisation process early on. Cook, stirring occasionally, until softened – around 15 minutes. Keeping the heat at medium during the initial stages helps to prevent burning. Continue cooking, stirring every few minutes, until they turn deep golden brown and jammy, which should take roughly 30 to 45 minutes more.
Lindsey highlighted that the biggest mistake people make when learning how to caramelise onions is rushing the process. If they begin to brown too rapidly, reduce the heat. Proper caramelisation should take time. It usually takes 45 to 60 minutes to "properly caramelise onions". Quicker methods often lead to uneven browning or burning.
Take off the heat and season with salt and pepper. Stir thoroughly and use straight away or store.
