Preheat oven to 325 degrees.  Butter 9 x 2 inch round cake pan.  Line the bottom with a circle of parchment paper and oil it lightly.

Cream butter, sugar, egg yolks, zest, and hazelnut and orange extracts until light and fluffy.  Add ground hazelnuts and stir until well-combined.  Beat egg whites until foamy.  Add cream of tartar and beat until stiff but not dry.  Add large spoonful to butter mixture and stir to loosen batter.  Gently fold in remaining whites.  Turn into prepared pan and bake until edges of cake shrink slightly from pan about 40-45 minutes.  The cake with be soft in the center.

Let cool completely in the pan. Invert onto a serving platter and remove the parchment.  Just before serving, cut Saint James pattern (rising sun or other design) from waxed paper.  Set over cake and sprinkle with powdered sugar.  Gently remove paper.  Serve, if desired, with preferred garnishes: chopped/ground hazelnuts, orange zest, and/or orange marmalade/sauce.