Sift together flour, baking powder and salt. Beat egg whites until foamy in large mixing bowl. Add cream of tartar and 1/4 cup of maple syrup. Beat until whites form stiff peaks.
Combine egg yolks, 3/4 cup maple syrup, vanilla and sifted dry ingredients in a small bowl. Beat at medium speed 4 minutes. Fold egg mixture gently into beaten egg whites. Pour into greased 10 inch tube pan and bake at 350 degrees F. for 45 minutes. Invert to cool.