Step 1

Combine the cream, milk and vanilla bean in a medium saucepan. Bring to a simmer over medium heat (see microwave tip). Remove from heat and set aside for 5 minutes to cool slightly.

Step 2

Whisk egg yolks and sugar together in a heatproof bowl until thick and pale. Use tongs to remove bean from cream mixture. Use a sharp knife to scrape seeds into the cream mixture. Gradually stir cream mixture into egg mixture.

Step 3

Pour into a clean saucepan and place over low heat. Cook, stirring constantly with a wooden spoon, for 15 minutes or until the custard coats the back of the spoon. Transfer to a medium heatproof bowl. Set aside for 10 minutes to cool.

Step 4

Place blackberries in the bowl of a food processor and process until smooth. Use the back of a spoon to press the puree through a fine sieve into a small bowl. Discard seeds. Add blackberry puree to the custard and stir to combine. Place in a shallow metal container. Cover with foil and place in the freezer for 6 hours or until almost set.

Step 5

Roughly break up ice-cream with a metal spoon and transfer to a bowl. Beat with an electric beater until smooth. Quickly return to container. Cover with foil and freeze for 4 hours or until firm.