For the cupcakes
Preheat oven to 170°C.
Place hazelnuts on a lined baking tray and roast for 15 minutes in oven.
Remove hazelnuts from oven and while still hot place them onto one half of a clean towel. Fold over the tea towel and gently roll to remove the hazelnut skins. Once your hazelnuts are cleaned, chop them finely and set aside.
In a bowl beat together the sugar and butter with an electric mixer with the paddle attachment, until the mixture is light and fluffy.
On medium-low speed, add the orange extract and eggs one at a time making sure you beat well after each addition.
Add baking powder, baking soda and kosher salt to the mix. Now add sifted flour in three batches alternating with the buttermilk until well combined.
Gently fold through hazelnuts.
Spoon the mixture into the paper cupcake cases until two-thirds full and bake in the preheated oven for about 20-25 minutes or until the center of the sponge bounces back when touched. (I like to use a paper cupcake case which I place into a normal cupcake tray, as it makes it much easier to remove them once cooked.)
Leave the cupcakes to cook slightly in the trays before turning out onto a wire cooling rack to cool completely.
For the chocolate frosting
Beat the icing sugar, cocoa powder and butter in an electric mixer with paddle attachment until completely combined.
Add milk slowly to incorporate on low speed.
When all combined turn up to high speed and beat for around 7 minutes until mixture is light and fluffy. Don’t over beat.
Icing can be piped on or spread with a knife across the top of the cupcake. Do whatever you find easier! I like to top my cupcakes with a dehydrated orange slice. These are easy to find at your local health food store or gourmet local delicatessen.