Prepare the Pomegranate Mousse: Combine pomegranate juice and sugar in a saucepan over low heat, stirring until sugar dissolves. Sprinkle gelatin and mix until dissolved. Cool slightly and fold in whipped cream. Chill for about 2 hours or until set.

Make the Sponge Cake: Preheat oven to 350°F (175°C). Whisk eggs and sugar until pale and fluffy. Fold in flour, melted butter, and vanilla extract. Bake for 20-25 minutes until golden.

Construct the Domes: Cut cooled sponge cake into circles, place in dome molds, pour mousse over, and freeze for at least 4 hours.

Prepare the Mirror Glaze: Combine pomegranate juice, sugar, and white chocolate in a saucepan until smooth. Mix in corn syrup and gelatin until blended. Cool to 90-95°F.

Glaze the Domes: Remove frozen mousse domes, place on a rack, and pour glaze over each, allowing excess to drip off. Chill for 30 minutes before serving.