In a food processor, combine the flour, baking powder, 50 grams of white sugar, and butter until the mixture resembles crumbs.
Set aside one third of the crumb mixture and mix in an additional 30 grams of sugar to create the crumble topping.
Press the remaining crumb mixture into the base of a 20 cm cake tin to form the pie crust.
Whisk the remaining crumb mixture with 3 teaspoons of eggs until it forms a cohesive ball of pastry.
Wrap the pastry ball in plastic wrap and chill it in the refrigerator for 30 minutes.
After chilling, roll out the pastry and fit it into the prepared cake tin.
In a bowl, mix the defrosted apples with 15 grams of cornflour and 60 grams of soft brown sugar.
Pour the apple mixture into the pastry-lined tin and sprinkle the crumble topping evenly over the apples.
Bake the pie in a preheated oven at 200 °C (fan) for 20 minutes.
Lower the temperature to 175 °C and continue baking for an additional 30 minutes.
Once baked, allow the pie to rest for 5 minutes before carefully removing it from the tin and transferring it to a wire rack to cool.
