Coconut Flan Croissant Tart

Combine the yeast, milk, bread flour, cake flour, salt, sugar, cold water, and butter. Knead using a stand mixer on low speed for about 5 minutes, then increase to high speed and continue kneading for 15–20 minutes until the dough is smooth and no longer sticks to the bowl. 

Take a portion of the dough (300 g) and knead it with the cocoa powder and a small amount of water. Mix until smooth, then roll into a thin sheet (2 mm). Chill until set. 

Roll out the main croissant dough into a flat sheet approximately 30 cm × 60 cm. Place the chocolate dough sheet on top, cover tightly with cling film, and refrigerate for 30–45 minutes. 

Roll the croissant butter (1 kg) into a 30 cm × 30 cm square. Place the butter sheet onto the rolled dough, cover with cling film, and refrigerate for about 30 minutes. The butter and dough should both be at around 5–6 °C for optimal lamination. 

Roll the dough into a sheet about 30 cm long and give it a single fold (letter fold). Rest in the refrigerator for 30 minutes. 

Roll and fold the dough again using a double fold (book fold). Rest for 90 minutes.

Using a sharp knife, cut the laminated dough lengthwise into even strips about 1 cm thick. Stack the strips onto the uncut dough sheet and press gently to adhere. Use a rolling pin lightly—do not press too hard to avoid damaging the layers. Roll the dough to a thickness of 3–4 mm, cut into pieces (10 cm base, 30 cm length), roll up from the base, and place into round moulds as shown. 

Proof for about 2 hours at 26 °C. Before baking, gently press the centre to create a "well" for the flan. Bake at 200 °C for 14–16 minutes until almost fully baked. 

Pipe the flan filling into the centre (25–30 g), then bake again at 160–170 °C for 8–10 minutes. 

Bloom the gelatine in cold water for at least 10 minutes. Meanwhile, heat the coconut milk, whipping cream, and salt until hot. 

Whisk the egg yolks with sugar until pale. Gradually pour the hot cream mixture into the egg yolks while stirring continuously. Return the mixture to the saucepan and cook over low heat, stirring constantly, until thickened or reaching 82–84 °C. 

Remove from heat, add the bloomed gelatine, and stir until completely dissolved. Strain through a fine sieve, then add the coconut meat. Mix well and allow to cool. 

Gently mix the eggs with sugar, avoiding incorporating excess air. Add coconut milk, vanilla extract, and salt, then stir until well combined. 

Strain the mixture at least twice before pouring into silicone molds.

Bake in a water bath at 150°C for 35–40 minutes. Allow to cool.