Caramelising onions at home is very easy to do and the results are a cut above anything you can buy in a jar. Sweet and sticky with a subtle hint of toffee-like flavour, these onions will lift an array of dishes – pile them into a sandwich, stir through pasta or dollop on top of a pizza. They will keep for around a week in an airtight container.

Instead of deglazing the pan with water try using vinegars such as Balsamic and sherry, or alcohol such as brandy or port. For extra sweetness add a little brown sugar at the end of cooking and cook until caramelised. You can experiment with different types of onion too; red onions and shallots both work very well.

Marcus Wareing adds caramelised onions to his mini beef burgers, while Adam Gray uses them on his quick and easy tart with melting Stilton cheese. In Italy, the Cerea brothers use caramelised onions in their refined main course of Lamb loin and rhubarb compote – they also make up the base for Pascal Aussignac’s Pissaladiere.