Melt the fat and let it cool down. Coarsely chop 150 g walnuts. Grate chocolate. Put flour, baking powder, sugar, chopped walnuts, chocolate, fat, eggs, advocaat and milk in a large tuppet bowl with lid. Close the bowl well and shake vigorously for about 3 minutes.
Put the dough into a greased springform pan (26 cm Ø) sprinkled with breadcrumbs and smooth it down. Bake in a preheated oven (electric: 200 °C/ gas: level 3) for approx. 45 minutes. Cover at the end of the baking time if necessary. Let the cake cool down on a cake rack. Place the bag with the cake glaze in hot water for about 10 minutes. Roughly chop the remaining nuts. Remove the cake from the tin and place it on the cake rack. Cover cake with icing and sprinkle with nuts. Leave to dry.
Roughly chop the remaining nuts. Remove the cake from the tin and place it on the cake rack. Cover cake with icing and sprinkle with nuts. Leave to dry. Serve with advocaat cream if desired. Makes about 16 pieces
waiting time approx. 2 hours