Preheat oven to 325.
Sift together flour, 3/4 cup sugar, cinnamon, ginger, cloves, nutmeg, baking powder and salt into a large bowl.
In a smaller bowl combine the egg yolks and pumpkin puree.
In a separate large bowl, mix the egg whites with an electric mixer until foamy. Mix in 1/2 cup sugar and continue to beat until eggs have formed stiff peaks.
Mix together the pumpkin puree and dry ingredients. Then fold in the egg whites in small batches.
Pour mixture into a greased 11 x 7 pan.
Bake for 45 minutes or until a toothpick comes out clean. Remove cake from oven and let cool for 5 minutes in pan. Then invert onto a cooling rack. Let cool completely.
Cream together butter and sugar. Mix in pumpkin, vanilla and cinnamon. Beat until light and fluffy then spread evenly on top of cooled cake. Next slice cake and enjoy!