Preheat the oven to 180°C (356°F).
In a bowl, combine the egg whites and sugar.
Sift in the almond flour, rice flour, and cocoa powder, and add them to the bowl.
Add the melted butter and soy milk, and mix well until smooth.
Pour the batter evenly into financier molds.
Bake in the preheated oven at 180°C for 15–18 minutes.
Cool on a wire rack.