Apple Crumble and Custard Tart

INGREDIENTS
For the pastry:

• 140g butter, chilled
• 200g plain flour
• 50g rolled oats
• 50g caster sugar
• 50g demerara sugar
• 1 egg, beaten

For the filling:

• 250ml milk
• 250ml double cream
• 1 tsp vanilla extract
• 100g caster sugar
• 8 egg yolks
• 3 pink apples

INSTRUCTIONS

1. Preheat the oven to 160c.
2. Rub the butter and the flour together until it resembles breadcrumbs. Add the oats, sugars and egg and bring together to form a dough. 
3. On a lightly floured surface roll out the pastry and line a 20cm tart tin. Prick the base and leave to chill for 30 minutes.