Prepare the Gelatin: In a small bowl, sprinkle the gelatin powder over 50ml of cold water and let it bloom for about 5-10 minutes until it becomes spongy.
Make the Sugar Syrup: In a medium saucepan, combine the granulated sugar and 50ml of water. Heat over medium heat, stirring constantly until the sugar dissolves completely. Bring the mixture to a gentle boil and then remove it from the heat.
Melt the Chocolate: In a heatproof bowl, melt the white chocolate either over a double boiler or in the microwave, stirring occasionally until smooth.
Combine Ingredients: Add the bloomed gelatin to the hot sugar syrup and whisk until the gelatin is completely dissolved. Then pour this mixture over the melted white chocolate. Stir until well combined.
Blend the Mixture: Transfer the mixture to a blender or food processor and blend until smooth. This step helps to ensure a smooth and glossy finish to the glaze.
Strain the Mixture: Pass the blended mixture through a fine sieve to remove any lumps or air bubbles. This step is crucial for achieving a perfectly smooth mirror glaze.
Cool the Glaze: Allow the glaze to cool slightly until it reaches around 90°F (32°C). This temperature is optimal for pouring over cakes.
Color (Optional): If desired, add food coloring to achieve the desired hue. Gel food coloring works best for mirror glazes as it won't affect the consistency of the glaze.
Glaze the Cake: Place your cake on a cooling rack set over a baking sheet to catch any drips. Slowly pour the glaze over the cake, starting from the center and working your way outward, ensuring the entire surface is covered.
Smooth the Surface: Use a spatula to gently smooth the surface of the glaze, working quickly before it begins to set.
Allow to Set: Let the glazed cake set at room temperature for about 10-15 minutes, or until the glaze is firm to the touch.
Serve: Once the glaze is set, transfer the cake to a serving platter and enjoy!