Chia seeds are soaked in water for 15 minutes. The butter and 100 g of melted chocolate and leave to cool slightly side. Beets peel, cut into cubes and grind in a blender along with the soaked seeds and vanilla. flour and cocoa are screened and mixed with sugar, 100 g chopped chocolate and orange peel. The three mixtures were combined and poured into a form with size 20x20 cm, covered with baking paper. Smooth the surface well. Bake in a preheated oven at 180C, about 30 minutes or until a crust on the surface. After cooling completely, the cake is cut into squares and sprinkle with cocoa.