What Can I Use Instead Of Onion For Tarts And Quiches?

Our answer

Nigella's Onion Tart (from HOW TO EAT) is a type of quiche made with a filling of softened onions, eggs and crème fraîche. The onions are cooked with a little Marsala wine to add extra flavour and to help caramelise them slightly. Nigella suggests red onions as an alternative, they are sweeter than regular onions but may not be suitable depending on tastes.

Shallots are also milder and sweeter than onions, so they could possibly be an alternative. Another alternative could be leeks, which are also a member of the allium family but are much milder than onions and shallots and have a slightly different texture. Cut the leeks lengthways and make sure that you wash them thorougly to remove any sand or grit that may be sitting in between the layers, then slice the leeks very thinly. Most people use the white and pale green parts but not the tougher dark green parts. You can soften the leeks in the butter and oil in a frying pan over a low heat. They tend to catch more easily than onions, so keep an eye on them. For the tart you can add marsala or you could use dry white vermouth instead. Turn up the heat and cook until caramelised, but again watch carefully as the leeks can burn more easily.