Preheat oven to 150 degrees C. Line bottoms of two 23cm cake tins with greaseproof paper.
To Make Cake: Melt 375g dark chocolate in the top of a double boiler or in a microwave. Cool and beat in egg yolks.
In a large bowl, beat butter or margarine, 1 1/2 cups sugar and vanilla until light and fluffy. Add chocolate mixture and continue beating until smooth. Stir in flour until just combined.
In another bowl, beat egg whites until foamy. Gradually beat in 1/2 cup sugar and continue beating until the whites hold soft peaks. Fold whites into chocolate batter, in three additions. Pour batter into prepared pans and smooth tops.
Bake until a toothpick stuck into the centers of the cakes comes out with moist crumbs, about 45 minutes. Cool in pans.
To Make icing: In a saucepan, bring cream just to a boil. Chop 185g extra dark chocolate and stir into the cream. Remove saucepan from heat and continue stirring until smooth. Pour icing into bowl and press a sheet of cling wrap directly against surface of chocolate to prevent formation of a skin. Refrigerate until thick enough to spread.
To Make Filling: Drain the thawed raspberries, if necessary, and combine with the jam. Sandwich the cake layers with raspberry filling. Spread top and sides with chocolate icing.