Mix sugar and cinnamon together in a small bowl and set aside.

Mix nutella and mascarpone together in another small bowl and set aside.

Take two slices of bread and spread nutella filling in between the bread.

Bring bread pieces together into a sandwich, and spread as much butter as desired on outside of sandwich.

Bring pan to low heat and cook your sandwich until golden brown on each side.

While sandwich is heating, spread cinnamon sugar on a plate. Take sandwich off heat and roll in cinnamon sugar, generously covering each side. Enjoy!