Whisk egg and sugar until puffy and white. Mix the baking powder with the flour in a separate bowl. Melt the butter. Add butter, milk and the flour to the egg and sugar mix, stir gently.

Pour the batter into a large oven tray (30×40 cm) covered with grease proof paper.

Mix the cinnamon and sugar and pour half of it into a plastic bag. Peel and cut the apples in pieces. Put the apple pieces in the bag and mix with the cinnamon and sugar mix. Press the apple into the batter and sprinkle the rest of the cinnamon-sugar mix over the cake.

Bake in 200°C for 25 minutes.