Preheat oven to 200 degrees Celsius. Draw the template on a baking parchment and place it on a baking sheet. Set aside.
Place the egg white in a clean, dry and grease-free bowl. Using an electric mixer, whisk the egg white on medium-high speed until soft peaks form. Add in sugar, tablespoon by tablespoon, beating on high speed until a smooth and glossy mixture is obtained with semi-stiff peaks. Sift in the flour and fold in until fully incorporated. Fold in the melted butter as well. Transfer 3 tablespoons of the mixture into a small bowl and set aside.
Sift the cocoa and cinnamon over the remaining mixture and fold in until fully incorporated. Drop tiny spoonfuls of batter on the template and using a palette knife, spread onto the template. Drizzle a little bit of the reserved plain mixture over and use a toothpick to create a marbling effect.
Bake for 4 to 6 minutes until just set. Working quickly and carefully (take care not to burn yourself), use a palette knife to lift up the cookie and drape it over a rolling pin. Press down gently using the palette knife and the tip of your finger nail to form a curved shape. If the cookies has cooled and became hard before you can shape them, return the cookies back into the oven for another 30 seconds to 1 minute.
Let the tuiles cool completely then transfer them into an airtight container.