Mussels with saffron vinaigrette

Simmer 250ml dry white wine, 80ml white wine vinegar and 1/2 tsp saffron threads in a saucepan over mediumhigh heat until reduced by two-thirds (12-15 minutes). Remove from heat, stir in 2 tsp caster sugar to dissolve, whisk in 80ml olive oil, season to taste and cool to room temperature. Cook mussels in a saucepan over high heat until just open. Remove mussels from shells, clean half the shells and place a mussel in each. Drizzle over saffron vinaigrette and serve on a bed of rock salt, paired with a glass of perfectly chilled Bollinger R.D. 2007.