Preheat oven to 180 degrees C. Lightly grease the bottom of one 23cm springform pan.
Reserve 8 whole nuts for garnish. Pulse the remaining nuts in a food processor until ground and reserve 1 tablespoon of ground nuts for garnish.
Melt margarine or butter in a small saucepan over low heat, cool.
In a large bowl beat eggs, sugar and 1 teaspoon vanilla essence until thick and lemon coloured (about 2 to 3 minutes). Add flour, baking powder, salt and ground nuts, mix well. Continue to beat mixture while slowly adding the cooled melted butter or margarine until blended (mixture will be thick). Spread batter into prepared pan.
Bake at 180 degrees C for 35 to 40 minutes or until a toothpick inserted in the centre comes out clean. Cool in pan for 15 minutes then remove sides of pan. Remove pan bottom and invert onto a serving plate. Cover with a cloth towel and cool for another 30 minutes before glazing.
To Make Glaze: In a medium saucepan bring whipping cream just to a boil, remove from heat and stir in the semi-sweet chocolate chips until melted and smooth. Stir in 1/2 teaspoon vanilla essence. Spread glaze over top of cooled cake, allowing it to run down the sides. Sprinkle reserved ground nuts around top edge and arrange whole nuts over ground nuts. Enjoy!