Mini castella cake: the soft, gourmet dessert

Ingredients:
40 gr butter
70 gr milk
40 gr honey
5 egg whites
110 g sugar
5 egg yolks
Vanilla extract
120 g flour

Directions:
Melt butter and mix with milk and honey.
Whip the egg whites with the sugar, then add the yolk, vanilla and flour. Mix 4 tablespoons of batter with the butter mixture, then combine. Pour batter into mini pans and bake at 320°F (160°) for 7 minutes, 300°F (150°) for 15 minutes.