White chocolate panna cotta with stewed rhubarb

Name: White chocolate panna cotta with stewed rhubarb
Cook time: 45 min
Total time: 45 min
Cuisine: European, British
Ingredients: 4 leaves fine leaf gelatine; 400ml double cream; 300ml whole milk; 70g caster sugar; 1 vanilla pod halved and seeds scraped out, or vanilla bean paste 1 tsp; 150g white chocolate finely chopped; 400g rhubarb cut into 2cm pieces; 50g caster sugar; 1 lemon juiced