Apple Cinnamon Ice Cream

1 large cinnamon sticks -- or 2 small
300 milliliters milk
4 large egg yolks
100 grams caster sugar
1/2 teaspoon vanilla extract -- or 1 tsp vanilla essence
300 milliliters double cream
2 crisp tart eating apples -- peeled and diced
1 teaspoon ground cinnamon
50 grams unsalted butter

Heat the cinnamon sticks in the milk until almost boiling. Remove the pan
from the heat, cover and leave for 20 minutes. Whisk the egg yolks and
sugar together until thick and pale. Discard the cinnamon sticks, then
reheat the milk, and continue making the custard following the blueprint
for Vanilla Ice Cream, from step 2.

Prepare the cinnamon apples while the custard is cooling. Toss the chopped apples in the ground cinnamon. Heat the butter in a frying pan, and wait until the foam subsides, then add the apples with any remaining cinnamon and fry quickly until they just start to soften, stirring continuously.
Allow to cool completely.

Freeze-churn the ice cream until well thickened, then gradually add the
cold apples while the ice-cream machine is still running, continuing
churning until the ice cream is ready to serve.