Preheat oven to 350 F. Smear with butter 9" or smaller bundt cake pan. Sprinkle some flour.
In a medium bowl combine all-purpose flour, almond flour and baking powder. Set aside.
In a separate large bowl mix with electric mixer butter and sugar until smooth. Add eggs, each at a time and mixing all the time. Combine all ingredients very well. Add vanilla extract.
Add dry ingredients to wet ingredients and combine with spatula.
Bake for 40 minutes until inserted toothpick will come out clean.
Remove from oven. Leave it for 10 minutes in the pan. Remove from the pan and cool off on wire rack.
In a medium bowl combine powdered sugar with lemon juice. Add about 2 tablespoons of water, check consistency. If it requires more water add one more tablespoon. Check consistency again, if it is too thick add one more tablespoon.
Glaze the bundt cake. Sprinkle some slivered almonds on top.