Sour Cherry Sauce
Preheat oven to 350 degrees F.
Sift together flours and baking powder. Stir in ground almonds.
In a food processor combine flour mixture with cold butter. Pulse several times until mixture resembles coarse meal.
In a small bowl whisk together whole egg, egg yolks and sugar until smooth.
Add to flour mixture and pulse again until mixture comes together.
Turn onto a lightly floured surface. Divide dough in half. Roll out each half into quarter inch thick 10-inch circles.
Cover with plastic wrap and chill for 30 minutes.
In a medium bowl whisk together first amount of milk, egg yolks and cornstarch until smooth.
Heat second amount of milk, sugar and vanilla in a heavy bottomed pot. When this mixture comes to a boil, slowly pour half of it over the egg yolk mixture while whisking briskly. Return mixture back to pot. Continue whisking 4 to 5 minutes until smooth and boiling. Remove from heat.
Add ground almonds.
Cover surface with plastic wrap. Cool to room temperature.
Line a flan ring with one layer of the rolled pastry. Pour in pastry cream and then top with second layer of pastry. Place flan ring on baking sheet. Bake for 40 to 45 minutes until golden and set.
Combine all sauce ingredients in a small saucepan and bring to a boil. Reduce to simmer and reduce by half. Strain and serve warm over cake.