For the syrup: Heat the sugar, honey, water, and brandy over medium-high heat until the sugar has dissolved. Turn heat to low and add in cloves, cinnamon stick, and orange rind. Simmer for 5 to 6 minutes and remove from the heat. Remove the orange, cloves and cinnamon stick and cool.
Preheat oven to 350 degree F.
For the Cake: In a medium bowl mix together walnuts, flour, baking powder, cinnamon, and clove.
In a medium bowl, with an electric mixer, whip together the butter and sugar until fluffy. Slowly add in the egg yolks and continue whipping. Add in the walnut mixture slowly, and mix until well blended.
In a very clean bowl, with an electric mixer, whip the egg whites until soft peaks form. Fold the egg whites into the batter until the mixture is completely incorporated.
Grease a 12 by 9-inch baking pan. Pour the batter into the prepared pan. Place the pan in the oven and bake until the cake is golden brown, about 45 minutes. Remove from the oven and pour the syrup over the cake, until it is drenched in syrup. Cover with a kitchen towel and let cool. Cut into diamonds and serve.