Preheat oven to 300 degrees. Line a baking sheet with parchment paper and set aside.
In a large bowl, beat egg whites until stiff peaks form (about 2 minutes). Add confectioner's sugar and beat until fully incorporated and glossy. Add vanilla extract and mix until combined.
In a separate bowl, combine dry ingredients - ground hazelnuts, salt, and cinnamon. Add dry ingredients to meringue and gently fold in until evenly incorporated.
Using a medium cookie scoop, two spoons, or a piping bag, drop into 1.5 tablespoon heaps onto lined baking sheet. Top each cookie with a whole hazelnut.
Bake for 23-25 minutes, or until edges are lightly browned.
Allow cookies to cool completely before removing from baking sheet to a cooling rack. If cookies stick to baking sheet or feel sticky to the touch, they need more time in the oven.
To make your own ground hazelnuts - place whole hazelnuts in a food processor and pulse until the desired texture is achieved. You're looking for a coarse texture similar to a meal, but not as fine as a flour. Macaroons can be stored in an airtight container at room temperature for up to a week. Macaroons can also be refrigerated if you don't plan to enjoy them right away - up to two weeks. Baked macaroons can also be frozen for up to a month.