Preheat oven to 350F, grease, and line the bottom of 4-6" pans with parchment paper. Set aside.
In a medium bowl, sift the flour, baking powder, baking soda, then hazelnut powder, and mix with a fork to combine. Set aside.
In a large measuring cup, mix the milk, sour cream, vanilla, and Frangelico and mix to combine.
Place the butter and sugar in a bowl of a standing mixer and beat using the paddle attachment on medium speed until light and fluffy. 4-5 minutes.
Scrape the bottom and sides of the bowl then increase speed to medium-high and add the eggs one at a time, waiting for each egg to be completely incorporated before adding the next.
Add the flour mixture in 3 additions alternating with the liquid. Starting and ending with the flour.
Once you added the last part of the flour, turn the mixer off add the chopped hazelnuts and chocolate chips, and use a rubber spatula to combine it all.
Dived the batter between the greased pans and bake for 28-30 minutes or until a toothpick comes out clean from the center of the cake.
Remove cakes from the oven and allow to cool before removing from the pan.