Preheat oven to 325°F (165°C). Do not grease your 10-inch tube pan.
Sift together the cake flour and ¾ cup of the superfine sugar at least three times. Set aside.
In a stand mixer, whip the egg whites, cream of tartar, and salt on medium speed until frothy.
Increase speed to medium-high and slowly add the remaining ¾ cup superfine sugar, one tablespoon at a time, until soft, glossy peaks form.
Gently fold in the vanilla extract, almond extract, and freeze-dried raspberry powder.
Sift the flour mixture over the meringue in four batches, gently folding it in with a rubber spatula. Fold in the fresh raspberries during the last batch.
Spoon batter into the ungreased pan. Run a knife through to remove air pockets.
Bake for 40-45 minutes until golden brown and springs back to the touch.
Immediately invert the pan and let cool completely upside down for at least 2 hours before removing from the pan.
