Line a large 12 hole muffin tray with cupcake cases.
Place all ingredients into the bowl of an electric mixer and beat on a low speed to combine. Increase the speed and beat for 3-4 minutes.
Spoon mixture into cases to two thirds full. Bake for 20-25 minutes. Cool.
Frosting: Place the cheeses, juice and butter into the bowl of an electric mixer. Beat for 6-8 minutes, until light and fluffy. Pipe onto the cooled cupcakes. Sprinkle with the pistachios.