Add cake flour, almond flour, powdered sugar, a pinch of salt, and cold unsalted butter (cut into cubes) into a food processor.

Pulse in short bursts until the butter particles are very small and no longer visible.

Add the egg and continue pulsing in short bursts until the dough starts to clump together.

Once large clumps form, stop and transfer the dough to a work surface.

Press and knead the dough with a scraper to ensure all ingredients are evenly mixed and achieve a uniform texture.

Shape the finished dough into a round, flat form, wrap it in plastic wrap, and let it rest in the refrigerator for at least 1 hour.

After resting, the dough will be hard; apply physical force to roll it out, dusting with additional flour as needed, and beat with a rolling pin until soft.

Roll the dough into a thin, round shape, turning it in eight directions to maintain its circular form, using additional bench flour to prevent sticking.

Check the size of the dough by comparing it to the tart mold; it should be large enough to cover the bottom and sides.

Use a 3mm square bar to ensure even thickness while rolling out the dough.

Quickly place the dough into the mold, pressing it against the sides to secure it, folding excess dough outward.

Roll the rolling pin over the top to cut off excess dough, then press the edges with hands to ensure the curved corners adhere to the mold.

Use a fork to poke holes in the bottom to prevent it from rising during baking.

Chill the dough in the freezer for 10-15 minutes to fully harden, then bake at 170°C for 15 minutes with pie weights.

Remove pie weights and bake for an additional 10 minutes at 170°C to ensure even cooking.

While the tart is still hot, sprinkle white couverture chocolate over it and melt it with residual heat, then brush it evenly inside the tart to coat.

Let the coated tart cool in the refrigerator to harden.

Place unsalted butter, dark brown sugar, all-purpose flour, baking powder, and salt into a food processor.

Use the pulse function to mix until it forms small clumps like streusel.

Transfer to a bowl, chill in the freezer for 10-15 minutes to harden, then bake at 170°C for 13 minutes to prevent spreading.

While still hot, chop the baked crumble with a scraper to make small crumbs that will adhere well to the tart edges.

Let the crumbs cool completely before using.

Add granulated sugar to egg yolk and whisk well.

Scrape the vanilla pod and add it along with corn starch to the mixture, whisking well to avoid lumps.

Heat whole milk in a saucepan until the edges start to simmer.

Gradually add the hot milk to the egg mixture, whisking well to prevent the yolk from cooking.

Return the mixture to the saucepan and heat over medium heat, stirring constantly with a whisk until it thickens and forms lumps.

Continue whisking vigorously to break up lumps and achieve a smooth custard cream.

Once it starts boiling with large bursting bubbles, remove from heat.

Strain the hot custard through a sieve immediately.

Cover the surface tightly with plastic wrap to prevent air contact and cool quickly in the freezer until the surface feels cool (about 10 minutes), then refrigerate.

Whip the heavy cream until stiff peaks form, ensuring it is firm enough for piping later.

Make Diplomat Cream by mixing the whipped cream into the cooled custard in two portions, starting with 1/3 and mixing well to avoid lumps, then adding the rest and stirring gently.

Store the finished Diplomat Cream in the refrigerator until ready to use.

Prepare Genoise by cutting a 1cm thick piece to a 12cm diameter (can be made ahead and stored in the freezer).

Slice bananas into 3.5cm long pieces just before use to prevent browning.

Spread a layer of Diplomat Cream on the bottom of the tart shell evenly.

Arrange the sliced bananas tightly like columns inside the tart, leaving the edges slightly loose for easier cream application.

Fill the gaps between bananas and edges with more Diplomat Cream, spreading it evenly on top to adhere to the Genoise.

Place the sliced Genoise on top, then spread more cream over it to form a gentle dome shape.

Transfer the remaining cream into a piping bag with a No. 805 tip and pipe around the tart edges in a petal-like shell pattern (3 tiers work well for this mold).

For decoration, halve baby bananas (or regular bananas), sprinkle with sugar, and caramelize with a torch, repeating the process twice for a longer-lasting caramel coating.

Place the caramelized bananas in the center of the tart.

Finally, attach the cooled crumble to the edges of the tart to complete the assembly.