Double chocolate tart

Name: Double chocolate tart
Ingredients: 175g/6oz plain flour, plus extra for dusting; 115g/4oz unsalted butter, chilled and cut into cubes; 2 tbsp caster sugar; 1 free-range egg, beaten; 200g/7oz good-quality white chocolate, broken into squares; 100ml/3½fl oz double cream; 200g/7oz good-quality milk or dark chocolate, broken into squares; 150ml/5fl oz double cream; 50g/1¾oz good-quality white chocolate, broken into squares; 150g/5½oz good-quality milk chocolate; 25g/1oz butter; 125ml/4fl oz double cream; 1 tbsp caster sugar; 1 tbsp amaretto liqueur; pinch sea salt; 210g/7oz marzipan