Position an oven rack in the center of the oven.
On a work surface dusted with tapioca flour, roll out the dough to a
For the filling: In a medium bowl, combine the egg yolks, sugar, and cornstarch. Using an electric mixer fitted with the whisk attachment, beat the egg yolk mixture on high speed until thickened enough that a slowly dissolving ribbon forms on the surface when the beaters are lifted.
In a small, heavy saucepan, heat the milk over medium-low heat until bubbles form around the edges of the pan. Gradually whisk the hot milk into the egg mixture. Return the mixture to the pan and cook over medium-low heat, whisking constantly, until the whisk leaves lines in the custard. Remove from the heat and whisk in the almond meal, butter, and Amaretto until smooth. If not using immediately, cover by pressing plastic wrap directly onto the surface of the frangipane. To store, let cool, then refrigerate for up to 12 hours.
Fill the crust with the frangipane and smooth the top with an offset spatula.
Top the frangipane first with the blueberries and then with the currants. In a small saucepan, heat the jelly over low heat until runny. Using a pastry brush, gently brush the fruit with the warm currant jelly, giving the fruit a glistening touch.
Cut into squares and serve topped with whipped cream and garnished with mint sprigs.