the goods:
1 box yellow cake mix
1 package (3.4 ounces) instant pistachio pudding mix
1 and 1/2 cups cold milk
frosting:
1 cup cold milk
1 package (3.4 ounces) instant pistachio pudding mix
1 cup heavy cream
1/4 cup powdered sugar
roughly chopped roasted/salted pistachio nuts
Preheat oven to 350 degrees. Whisk together instant pudding mix and the cold milk. Sprinkle in the cake mix and mix well with a rubber spatula until combined. Line a muffin tin with paper cupcake liners. Fill each cup about 3/4 full with batter. Bake for 25 minutes and allow to cool completely before frosting.
To make the frosting, whip the cream with the powdered sugar until soft peaks form. Whisk together the instant pudding with the cold milk. Fold the the pudding into the whipped cream and pipe onto cupcakes. Top with chopped pistachio nuts.