• Chop up the chocolate bar into small pieces and melt into the milk. You can do this in a small bowl in a microwave or in a saucepan on the hob.
• In a separate bowl whisk the egg yolks with the caster sugar and a large pinch of salt, until it's thick and creamy.
• Pour the milk mixture gradually into the eggs mixture and carry on gently whisking.
• Add the cream and incorporate it into the mixture.
• Transfer everything into a large saucepan and bring to a simmering point over medium heat, whilst constantly steering or whisking.
• Carry on cooking for a few extra minutes until the mixture thickens.
• Pour it into your ice cream churn or pour it into a suitable container (for the freezer and to allow you to whisk the ice cream at the same time).
• At this point, you also have the choice of blending in the peanut butter now or leave it until the ice cream is completely churned and then marble in the peanut butter.

The ice cream churning process

• Place in the freezer initially for 30 minutes or until you see that the sides are starting to set.
• Take the container out of the freezer and whisk the ice cream mixture for few minutes.
• Place back into the freezer and leave for another 30 minutes or so.
• Repeat this process about 4 more times or until the mixture is nice and light and looking exactly like ice cream.
• Leave to freeze until you are ready to serve your ice cream.
• Use within 3 months.