Use on a frozen mousse cake
If using sheet gelatin: soak it in very cold water to rehydrate, about 10 minutes before starting the glaze preparation. Squeeze it well before adding it to the hot mixture.
If using powdered gelatin: bloom it in the indicated amount of cold water, at least 15 to 20 minutes before starting (keep it in the refrigerator). You will obtain what is called the gelatin mass.
Prepare the syrup: put the water, glucose, and sugar in a saucepan. Heat until it reaches 103°C (217°F), stirring occasionally without splashing the sides. If this happens, clean the sides of the pan with a damp brush.
Pour the hot syrup through a strainer over the condensed milk and coloring, then add the squeezed gelatin (if using sheets) or the gelatin mass (if using powder).
You can also add the coloring after blending, which allows you to divide the glaze into several parts and color them differently.
Mix gently with a spatula, then pour over the chocolate placed in a tall, narrow container (like a measuring jug or the container provided with your immersion blender).
Wait a minute before stirring gently with the spatula.
Blend for 3 to 4 minutes with an immersion blender. This step is crucial: to avoid creating bubbles, slightly tilt the container and always keep the blender immersed without removing it, except at the end.
You'll notice that the more correctly you blend, the more shiny and fluid the glaze becomes.
Pour the glaze through a fine sieve into an airtight container, then cover it with plastic wrap touching the surface. Place in the refrigerator until the next day.
The next day, pour the glaze into a saucepan and gently heat it to a maximum of 38-40°C (100-104°F), using a double boiler or in the microwave.
Remove regularly from the double boiler (or microwave), stir, then put back to heat. This allows you to control the temperature and melt the mixture well without overheating it.
Note: If at 35-36°C (95-97°F) the glaze is almost entirely melted, it's perfect. The blending will finish melting the last pieces, allowing you to reach the ideal usage temperature more quickly.
Then pour into a tall, narrow pouring jug, and blend with an immersion blender to eliminate all bubbles. The glaze then becomes smooth and ultra-shiny: you can almost see yourself as in a mirror.