Heat the butter in a pan. Add the figs, sauté for approx. 5 mins. Add the wine, balsamic, sugar and salt, cover and simmer over a low heat for approx. 10 mins., stirring occasionally. Add the mustard seeds, thyme leaves, fennel seeds and pepper, puree.
Bring the fig mustard back to the boil. Ladle it into the clean, pre-warmed jars while still boiling hot, fill the jars to just below the rim, seal immediately. Leave to cool then store in the fridge for approx. 3 days to allow the mustard to release its full aroma.