First, roast your hazelnuts. Preheat oven to 350° Fahrenheit. Spread whole, unsalted hazelnuts on a cookie sheet and pop in the oven for 15-20 minutes until the outer skin peels away a bit. Remove and pour into a kitchen towel. Let cool a few minutes, then vigorously rub towel so that some of the hazelnut skins are removed, then let cool completely. Once the nuts are cool, blitz up in a food processor in small batches (1/2 cup MAX per blitzing round or else you'll end up with hazelnut butter) or nutribullet until you have roasted hazelnut flour.

In a medium bowl, whisk together the flour, hazelnut flour, starch, baking powder, and salt until combined. Set aside. In a large bowl, using an electric mixer, beat together the eggs, sugar, canola oil, and vanilla until thick and lighter. Pour the whisked dry ingredients into the egg/sugar bowl and stir together using a spatula until combined. Cover the bowl with plastic wrap and chill in fridge for at least 4 hours or overnight.

Bake for 13 minutes and remove to let cool completely before serving or eating.