Add the eggs and sugar to a deep bowl and mix on high speed for 5 minutes.

Add the vanilla essence.

Mix the baking powder with the flour.

Then gradually add the flour mixture to the bowl. Mix on low speed.

Prepare the walnuts.

Chop the walnuts in a blender.

Melt a knob of butter and use a pastry brush to grease the mold or baking tray. I used a silicone mold with a diameter of 20 cm.

Sprinkle a little walnut into the greased mold, or if using a baking tray, you can sprinkle the walnuts on top of the mixture.

Add the chopped walnuts to the bowl with the mixture.

Mix with a spatula.

Transfer the mixture into the mold and bake in a preheated oven at 180°C (350°F) for 25-30 minutes.

The walnut cake is ready. Sprinkle with powdered sugar if desired.