Estelle's wonderful apple cake

I made this for my friend Anna's birthday and we had it served at Jamie's Italien.
A super easy but super yummy cake. The recipe is courtesy of my dear Estelle.

You need (for a 20m cake):

8 tbsp. flour
8 tbsp. sugar
8 tbsp. milk
pinch of salt
3 eggs
5 tbsp. vegetable oil
3-4 apples

for the icing:
1 egg
100 g sugar
80 g butter
a bit of vanilla essence

Mix all ingredients and pour the batter in the tin. Cut the apples into relatively thin slices and place them on the batter (they will sink).

Bake for 20 minutes at 180 degrees (preheated).

Mix the icing and pour it over the cake. Bake for another 15-20 minutes until it looks golden and caramelized.