Preheat the oven to 325° F / 160° C / 140° Fan / Gas 3.
Line a muffin tin with 12 large muffin sized cupcake cases.
Cream together the butter and sugar until pale and fluffy.
Add the beaten eggs & the vanilla & mix beat together.
Add the flour & cocoa and mix thoroughly until smooth.
Then add the oil & milk and mix again until combined.
Finally add the chocolate chips, and stir until well mixed.
Spoon the batter evenly into the cases and bake for 25-30 minutes.
When baked remove from the tin and leave to cool on a wire rack.
Whilst they cool cream the softened butter together with Nutella and then add the icing sugar and cocoa, mixing together until creamy and lump free. Finally add the milk and whip together until smooth.
Once the cakes are cool pipe a swirl of buttercream onto each cupcake and top with a few chocolate curl sprinkles.
Made this recipe? Don't forget to tag me!@itssarahsibley I love to see all your tasty creations!