Preheat oven to 170 °C. Beat the butter with the mixer for 3 minutes, until fluffy. Add the cake mix and then the eggs. Beat for 3 minutes at a low tempo. Spatula the nuts into the batter.
Fill the muffin tin with the cupcake moulds Scoop the batter into the moulds.
Cut the apple into fours, remove the core and slice thinly. Insert the apple slices into the cakes. Sprinkle the Fudge blocks on top.
Place the cakes in the middle of the oven and bake them for approx. 20 minutes until golden brown and ready. Allow the cakes to cool off on a grid.
