Tamarind, a popular ingredient in Indian cooking, is the sour-tasting pulp of a tropical tree. It is dried and then pressed into blocks, which need to be mixed with hot water and strained to give a paste before cooking. However, it is now also available bottled in paste form, which is much more convenient. Here is an unusual savoury marmalade to accompany cooked meats. I serve it with foie gras, topped with cracked black pepper, but most cold meats would be suitable.
Heat the butter in a heavy-based saucepan until it begins to foam, add the celery and onion and season with salt and pepper. Stir in the sugar, cover the pan, then reduce the heat and cook for about 30-35 minutes, until the celery and onion become caramelised, stirring them occasionally. Uncover the pan, add the vinegar, red wine and tamarind and return to a low heat for 30 minutes, until the celery becomes slightly tacky in consistency, like marmalade. Serve hot or cold.