For the dough, beat the butter and sugar with the paddle on medium speed until very soft and light. Beat in the vanilla and the yolk and continue beating until smooth and shiny, about 3 more minutes. Stop the mixer, sift the cake flour and add to the butter mixture. Pulse the mixer on and off to incorporate the flour. Scrape the dough onto a piece of plastic, wrap and chill it until firm.
For the almond filling, combine almond paste, sugar, yolk and zest and beat by machine until smooth. Beat in butter, scrape bowl and beaters and beat in eggs. Continue beating until light.
Stir in flour. Divide the dough into 4 parts and roll one piece at a time on a floured surface. Use each piece of dough to line a 3 to 4 inch diameter tart pan. Mass the scraps together after rolling the dough for the first four pans and line the last two.
Arrange the sliced berries evenly on the crust in each pan, then top with the almond filling, spreading it evenly with a metal spatula. Strew evenly with the sliced almonds.
Bake the tarts at 350 degrees about 25 minutes, until dough is baked through and filling is set.
Cool in pan, unmold and dust with confectioners' sugar. Decorate each tart with a few whole berries.