Mix the butter, sugar and eggs until fluffy (you can also use normal granulated sugar, but it tastes better with powdered sugar). Then add the cinnamon, flour and baking powder (you shouldn`t skimp on the cinnamon). Finally add the grated nuts and chopped apples (I cut the apples into pieces about 0.5 cm). Then bake for about 50 minutes - 1 hour in the oven at 175 ° Celsius. To finish, sprinkle with a light layer of powdered sugar.