Ingredients 

1. ½ cup unsalted butter , at room temperature
2. 1 ½ cup sugar
3. 2 large eggs
4. 1 teaspoon vanilla
5. 2 ¼ cups all-purpose flour
6. ⅔ cup unsweetened cocoa powder , not dutch process
7. 1 teaspoon baking soda
8. ½ teaspoon salt
9. 1 cup hazelnuts , very finely chopped

Instructions 

1. Sponsored Content Rehydrate. Replenish. Refuel.By GatoradePreheat oven to 350 degrees F. Line a sheet pan with parchment paper.
2. In the bowl of a stand mixer fitted with a paddle attachment, beat together the butter and sugar on medium high speed until light and fluffy, about 3-4 minutes. Add the eggs, one at a time, mixing after each. Add the vanilla.
3. In a separate bowl, combine the flour, cocoa powder, baking soda, and salt. Add to the wet mixture in the stand mixer and mix on low until combined. Add the chopped hazelnuts.
4. Spoon onto the prepared baking sheet by rounded tablespoons. Bake until cookies are firm and cracked on top, about 10 minutes. Cookies will be very soft. Use a spatula to transfer them to a cooling rack and cool completely.