Preheat the oven to 170℃/ 340℉.
Put the room temperature unsalted butter and powdered sugar in a bowl, and cream with a whisk.
Beat the egg in a separate bowl and add it little by little to the big bowl. Mix to combine.
Add roasted and chopped walnuts to the dough, and mix. You can use your favorite nuts like almond and hazelnut.
Add flour and almond powder, mix them together until you can’t see any flour, but don’t over mix.
Cover the dough up with film, and let it cool in the fridge for at least two hours. Divide the dough with a knife and make small balls.
Place them onto an oven tray and bake in the preheated oven at 170℃/340℉ for 15 min.
Put them into a bowl with powdered sugar, cover the cookies with it while they are hot.