Add the chopped chocolate to a medium-sized heat-proof bowl and set it aside.
12 ounces semisweet chocolate
Heat the heavy cream in a small saucepan set over medium heat, just until it begins to steam. Pour the cream over the chocolate and allow it to sit for 1 minute.
1½ cups heavy cream
Stir the ganache until it comes together, about 1 minute.
Remove ⅓ cup of ganache to a small bowl and stir in the chopped hazelnuts.
¼ cup finely chopped roasted salted hazelnuts
Set the remaining ganache aside for 1 hour, or until it has cooled completely.
When the ganache is cool, beat it with a hand mixer on medium speed for 3-4 minutes, or until it becomes light and fluffy. If the frosting becomes grainy or wet, add 1 cup of powdered sugar and continue mixing until it comes together into a light and fluffy frosting.
Transfer the whipped ganache to a piping bag fitted with your choice of tip (I’m using a Wilton 2D).
To assemble, cut a small hole out of the center of each cupcake (about the size of a quarter) and fill it with the chocolate-hazelnut mixture. Then place the cut out piece of cake back on top and top the cupcake with whipped ganache.
Top each cupcake with an unwrapped Ferrero Rocher chocolate.
12 Ferrero Rocher chocolates