For the cupcakes:
¾ cup plus 2 tbsp. shelled pistachios, divided
10 tbsp. unsalted butter, at room temperature
3 oz. cream cheese, at room temperature
1½ cups sugar
3 large eggs
1 tsp. vanilla extract
1½ cups all-purpose flour
1½ tsp. coarse salt (I used fleur de sel)
For the ganache:
4 oz. bittersweet chocolate, finely chopped
½ cup heavy cream
2 tbsp. unsalted butter, at room temperature
Additional pistachios, for garnish
To make the cupcakes, preheat the oven to 325˚ F. Line cupcake pans with paper liners.
Place ½ cup of the pistachios in the bowl of a food processor. Process until finely ground. In the bowl of an electric mixer, combine the butter, cream cheese and ground pistachios. Beat on medium-high speed until light and fluffy, about 3 minutes. Gradually mix in the sugar on medium-low speed, scraping down the sides of the bowl as needed. Beat in the eggs one at a time, mixing well after each addition. Blend in the vanilla. With the mixer on low, add the flour and salt, and mix just until the dry ingredients are incorporated. Coarsely chop the remaining pistachios and evenly fold into the batter with a spatula.
Divide the batter evenly among the prepared liners, filling each about three quarters full. Bake, rotating halfway through baking, until a toothpick inserted in the center comes out clean, about 30 minutes. Let cool in the pan a few minutes, then transfer to a wire rack to cool completely.
To make the ganache, place the chopped chocolate in a small heatproof bowl. Bring the heavy cream to a simmer in a small saucepan over medium-high heat. Pour the warm cream over the chocolate and let stand 1-2 minutes. Whisk in small circular motions until the chocolate is completely melted and the ganache is smooth and glossy. Whisk in the butter until completely incorporated.
Dip the top of each cooled cupcake into the ganache to create a thin, even layer. (I like to let the ganache cool and thicken just slightly before dipping the cupcakes.) Sprinkle with additional chopped pistachios, if desired.