Preheat your oven to 350°F (175°C) and prepare two 9-inch round cake pans by greasing and dusting with flour.

In a food processor, finely pulse the hazelnuts, being careful not to create a paste.

In a mixing bowl, sift together the flour, sugar, cocoa powder, baking powder, salt, and ground hazelnuts.

Whisk together eggs, vegetable oil, milk, and extracts in another bowl until smooth.

Gradually pour the wet mixture into the dry ingredients and gently fold together.

Fold in the chocolate chips if using, then evenly divide the batter between prepared pans.

Bake for 30-45 minutes, checking for doneness with a toothpick.

Cool the cakes in the pans for 20 minutes, then transfer to a wire rack to cool completely.

Frost the layers with whipped cream or ganache once cooled, stacking and decorating as desired.