Bloom Gelatin: Stir gelatin into water in a small bowl and let sit for 5-10 minutes.
1 teaspoon powdered gelatin, 1 tablespoon water
Chop Chocolate: Finely chop milk chocolate and place it in a large heatproof bowl.
3 oz milk chocolate
Simmer Cream: Heat half the heavy cream in a saucepan until it begins to simmer (look for small bubbles around the edges), then remove from heat.
1 cup heavy cream
Dissolve Gelatin: Add gelatin to the hot cream and whisk until fully dissolved.
Combine: Pour the gelatin-cream mixture over the chocolate, let sit for a minute, then whisk until smooth.
Blend: Use an immersion blender to mix thoroughly for 1-2 minutes, ensuring no lumps remain.
Add Cream: Incorporate the remaining cream to cool the mixture, then blend for another minute.
Refrigerate: Cover the ganache with plastic wrap in direct contact and refrigerate for at least 6 hours, or overnight.
Whip: Whip the chilled ganache with a mixer until light and fluffy, about 3-5 minutes. The whisks should leave clearly visible trails. Stop immediately if you notice any graininess.
Pipe: Pipe the ganache immediately after whipping.