1. COMBINE flour, nuts, sugar and butter in a food processor and process just until mixture resembles breadcrumbs. Add the egg and process briefly until mixture begins to form lumps. Press into the base of a 23cm round fluted tart pan with a removable base and chill for 10 minutes. Prick well with a fork and then bake in a moderate oven 180°C for 20 minutes or until lightly golden around the edges. Reduce the oven to 160°C.
2. BEAT the egg yolks and extra 2 tablespoons sugar until pale and creamy.
3. COMBINE the cream, milk, ginger and vanilla in a small saucepan and heat to a simmer. Remove from the heat, add the chocolate and stir until smooth. Slowly add the chocolate mixture to the egg yolks, stirring until combined. Pour into the pastry case.
4. BAKE for 40-50 minutes or until just set. Cool in the pan on a wire rack before chilling for at least 1 hour.
5. SPRINKLE the top of the tart with remaining extra sugar, and then use a cook’s torch to melt and caramelise the sugar to form a toffee crust. Serve immediately.