Chocolate Italian Wedding Cupcakes - Cupcake Fanatic

Ingredients

• 1/2 cup butter, at room temperature
• 1/2 cup sugar
• 1/2 cup packed light brown sugar
• 3 eggs, separated
• 1 1/2 ounces unsweetened chocolate, melted and cooled
• 1 2/3 cup all-purpose flour
• 3 tablespoons Dutch-processed cocoa powder
• 1/2 teaspoon baking soda
• 1/4 teaspoon baking powder
• 1/4 teaspoon kosher salt
• 1/2 cup buttermilk
• 1 teaspoon vanilla
• 1/2 cup shredded sweetened coconut
• 1/3 cup finely chopped pecans
• 2 tablespoons crushed cocoa nibs
• 1 cup shredded sweetened coconut
• 1/2 cup finely chopped pecans
• 1 cup (about 6 ounces) semi-sweet chocolate, chopped (I used chips)
• 1/4 cup butter
• 1/2 cup sour cream
• 3 cups powdered sugar