Melt the chocolate in a water bath together with the butter and let it cool for 10 minutes. Slowly whisk the eggs with the sugar until the sugar dissolves. TIP: We do not want a white foam, so whisk slowly. Combine both mixtures and incorporate the flour. The resulting dough will keep refrigerated for 5 days. It can be stored directly in baking molds in the fridge or in a pastry bag in the fridge. Every mold is differently sized, but when the surface cracks during baking, it's done.