Preheat to 200°C, bake at 180°C for 13 minutes
Melt the butter over medium heat until it turns brown.
Mix almond flour, cake flour, and sugar together.
Add the egg whites and mix.
Pour in the melted butter and mix until well combined.
Pour the batter into the mold.
Bake in a preheated oven at 180°C for 15 minutes.