Grease and flour a 9 or 10 inch spring form pan and line the bottom with parchment paper if you like, for easier release. Preheat oven to 350 degrees F.

Sift together the flour, baking soda and baking powder and set aside.

Cream together the butter and sugar well. Add the vanilla extract.

Beat in the eggs, one at a time, beating well after each addition.

Fold in the dry ingredients alternately with the sour cream. I do this on low speed in my mixer.

Always begin and end with the dry ingredients when adding them alternately. I generally add the dry ingredients in 3 portions and the sour cream in 2 portions.

Spread the batter evenly into the prepared spring form pan. Arrange the peach slices so that they cover the surface and then sprinkle on the blueberries between the peach slices.

Sprinkle the sugar over the top of the cake and bake for approximately 1 hour. Deeper pans may take an additional 10 minutes or more. When a wooden toothpick inserted into the center of the cake comes out clean it is done. Avoid piercing the fruit when doing the toothpick test. That can tend to clean the toothpick on removal, and may give an inaccurate indication that the cake is done.

Cool the cake in the pan for about 15 minutes before removing the sides of the spring form pan and cooling the cake completely on a wire rack. If serving for brunch, I like to serve it warm, after at least a half hour out of the oven.