Custard base:

• In a medium-sized pan over medium heat, bring the half-and-half to a light boil.
• While waiting for the half-and-half to heat up, add the egg yolks and sugar into a small mixing bowl and whisk together.
• Once the half-and-half is ready, whisk about half a cup of it into the egg mixture. This step is necessary; to temper the eggs. Tempering the eggs prevents them from turning into scrambled eggs.
• Pour the egg mixture into the pan with the half-and-half, and carefully cook over medium heat, constantly stirring, until the mixture thickens. The custard needs to be thick enough to coat a spoon without it dripping down everywhere.
• Add the roughly cut up or broken up Toblerone to the custard and whisk until all the chocolate is melted. Then add the heavy cream and stir well.
• Place the pan in ice-cold water and stir to cool to room temperature.

• Once at room temperatur, cover and chill for 2-3 hours, or until thoroughly chilled.

Churning:

• Once cooled, add the custard mixture into the already running ice cream maker. Having the ice cream maker running prevents the mixture from sticking and freezing to the bottom and the sides.
• Freeze the mixture according to your ice cream maker's instructions. Mine takes about 35 minutes since it is a big batch. Shortly before the ice cream reaches soft serve consistency, add the Toblerone chunks. Churn for another 5-10 minutes, and then fill the soft serve ice cream into a big freezer-safe container and chill for at least two hours.