Preheat the oven to 375 degrees F. Line the bottom of the pan with parchment paper.
Grind the walnuts in a blender. (Keep few walnuts halves to decorate the cake.)
Using a mixer beat the eggs with sugar.
Add the butter. Mix.
Add the walnuts and almond powder. Mix.
Add the flour and mix last time.
Pour the batter in the pan. Lay slices the walnuts halves on top of the cake.
Bake for about 40 minutes or until а toothpick inserted in the middle comes out clean. Once the cake cools off, then transfer to plate.
Dust it with powdered sugar before serving.