INGREDIENTS
 

Filling
1-10 oz. package  sweetened frozen raspberries, thawed - do not drain
  (16.5 oz. canned raspberries may be used - see directions below)
 1-1/2 cups whole frozen marion blackberries, thawed - do not drain
  (16.5 oz. canned marion blackberries may be used - see directions)
5 Tablespoons sugar
3 Tablespoons cornstarch
1 Tablespoon lemon juice
1 Tablespoon water

Pastry
1-1/2 cups all-purpose flour
1 cup finely ground hazelnuts
3/4 cup sugar
1 teaspoon cinnamon
1/4 teaspoon ground cloves
1/2 teaspoon finely shredded lemon peel
1/2 teaspoon finely shredded orange peel
1 teaspoon baking powder
1-1/2 cubes butter (6 oz.), softened
1 egg
1 egg yolk

DIRECTIONS
 

Filling
Mix all filling ingredients in saucepan and simmer for 5-6 minutes, stirring gently until thickened.  Set aside to cool.  (If canned berries are used, drain, reserving 3/4 cup juice, and omit the additional 1 Tablespoon water in recipe.  Combine all filling ingredients in saucepan except berries, and heat until thickened.  Add berries at this point and set aside to cool.)

Pastry
Preheat oven to 350?.

Mix all dry ingredients, lemon and orange peel together. Using pastry blender, cut in butter very finely until mixture has the consistency of coarse sand.  Beat egg & yolk together.  Make well in center of dry ingredients, pouring in the beaten egg and blending with fork, until all dry ingredients are moistened - 2 to 3 minutes.  (It will be very soft.)  COOK’S NOTE:  The food processor method (i.e. cutting hard butter into flour mixture) is not recommended here, as it is essential to use softened butter to have a soft dough,  in order to pipe through pastry tube.

Assembly
Press half the dough in the bottom of a 9" tart pan with removable bottom, or 9" springform pan. Spread filling over dough.  Using a pastry tube fitted with a 3/8" plain or ridged tip?? pipe diagonal lattice over filling. Pipe a continuous border of large dots around outer edge where lattice intersects.  Bake at 350? for 35-40 minutes. Cool tart completely before attempting to unmold.  Dust with powdered sugar.