If so, you can substitute the same amount of finely ground hazelnuts, cashews, or walnuts. (landsandflavors.com)
I would have not thought to use ground hazelnut for a batter but it sounds perfect! (strengthandsunshine.com)
If you are in a hurry and do not have time to toast the hazelnuts, by - pass this whole process and use ground hazelnut directly. (frenchieandtheyankee.com)