Cashew Nut & Lemongrass Curry

The cashew tree, with its extraordinary-looking rainbow fruit and hanging curved seeds we erroneously call nuts, is a member of the sumac family. Native to Brazil, it was brought to Goa by the Portuguese in the 1560s, from where it spread to become a staple of South Asian cookery. In curries, the nuts are often ground into silky sauces, but in this rich and delightful Sri Lankan dish they get star billing: soft, sweet and plump with coconut milk.

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