Start by making the frosting: Use a mixer to cream softened butter; add melted chocolate and continue to mix. Slowly add powdered sugar and sour cream. Add vanilla and beat until smooth.
Remove frozen pound cake from freezer and unwrap. Spread frosting in a thick layer on top of the pound cake, adding more frosting around the edges of the pound cake in order to create a shallow well in the center to hold the caramel.
Fill shallow well with caramel. Top with peanuts. Place in the freezer to firm up for 30 minutes.
To make the ganache, place chocolate chips and whipping cream in a small bowl and microwave for 30 second intervals until melted. Let cool until slightly thickened.
Drizzle ganache over top of the pound cake and place in the refrigerator for 20 minutes till firm. Serve at room temperature.