For the white chocolate fudge:

1. Make the white chocolate fudge. Put the syrup, heavy cream, butter and salt in a medium heavy-based saucepan over low heat. Stir from time to time for 5 min with a silicone spatula until everything has melted and is combined. Take the saucepan off the heat and add the chocolate and vanilla extract. Stir until the chocolate has melted and is completely smooth.

    

2. Store. Scrape the fudge into a bowl, cover the bowl tightly with plastic wrap and let it stand until the fudge is at room temperature. Then place in the fridge until you’ll need it for the ice cream, preferably the day after.

For the chocolate ice cream:

1. Melt the chocolate and make the custard. In a large bowl, combine the chopped chocolate, cocoa powder and vanilla extract. In a medium heavy-based saucepan over medium heat, bring the coffee and 150ml (⅔ cup) of cream to just below a boil, stirring frequently. Pour the hot liquid over the chocolate and stir until completely smooth. Set a mesh strainer over this large bowl. In the same saucepan over medium heat, bring the 250ml (1 cup) of cream left, milk, sugar and salt to just below a boil, stirring frequently to make sure the sugar has dissolved. In a separate medium bowl whisk the yolks for 2 minutes, until they lighten. Slowly pour the hot milk/cream mixture into the yolks bowl while whisking constantly.

    

2. Cook the custard. Pour the egg mixture back into the saucepan and place it over low heat, stirring constantly with a spatula and scraping the bottom of the pan as you stir. If it’s too hot, the custard will curdle so be careful. Cook and stir it for 5 min until the custard thickens and coats the spatula or until the custard’s temperature reaches 80°C (176°F).

    

3. Pour the custard over the melted chocolate. Pour the custard through the mesh strainer into the melted chocolate bowl and whisk until smooth. Cover the bowl with plastic wrap, pressing it directly onto the surface of the chocolate custard and let stand until it’s at room temperature.

    

4. Churn the ice cream. Chill the custard thoroughly in the fridge for at least 8 hours but preferably overnight. Whisk the chilled custard until smooth and scrape it into your ice cream maker. Churn according to manufacturer’s instructions.

To assemble:

1. Layer up! Scrape one-third of the ice cream in a 1.5-liter container with a tight-fitting lid and spread it evenly. Spoon one-third of the white chocolate fudge randomly over the ice cream. Repeat layering until you run out of ice cream and fudge, ending with the fudge. Run the blade of a small knife through the layers in a zig-zag motion to create a swirl pattern.

    

2. Freeze. Cover the container with plastic wrap, pressing it directly onto the surface of the white chocolate fudge ice cream. Close the lid and freeze for at least 8 hours or overnight.