Zest 1 orange into a bowl and set aside. Cut the orange in half and juice each half into a separate bowl and set it aside. Weigh or measure into a medium bowl the flour, baking soda, baking powder, salt, and cocoa powder, then run a whisk through to blend. Set this bowl aside. In a small bowl, weigh or measure your white and light brown sugars and set this bowl aside.
In a stand or a handheld mixer and blend the butter and sugars for about 3 minutes. Scrape down the sides and add orange juice, orange zest, vanilla extract, and incorporate. Next, add one egg at a time and blend till smooth.
Turn the mixer down to low and gradually add the flour mixture to the bowl till all the flour is blended in. Stop the mixer and add the hazelnuts and turn the mixer back on for about 30 seconds or so to get the hazelnuts mixed into the batter. Cover and put into the refrigerator for 30 to 45 minutes.
Preheat your oven to 350° and line 2 cookie pans with parchment paper. (I have not cooked these cookies with silicone mats, so not sure how they will turn out.) I use an OXO Good Grips Cookie Scoop Small because I like small cookies that are easy to handle, but you can make bigger ones but add a minute or two to the baking time. I add a few hazelnuts to the top and press in slightly.
Put into the oven and bake for 12 to 14 minutes. Watch for them to start to crack on the top just a little then pull them out. Leave them on the pan for a minute or two before moving them to the cooling rack.