Red Onion Marmalade

Melt the butter in a medium-sized saucepan, stir in the chopped onions and the thyme and let them soften for about 10 minutes.

Then add the wine and wine vinegar, bring it all up to a gentle simmer and add a seasoning of salt and freshly milled black pepper. Turn the heat to its lowest setting and let the whole thing cook really slowly with the lid off for about 50 minutes to 1 hour or until all the liquid has evaporated. Remove it from the heat, but re-heat gently before serving