Base of chocolate, pecans, and coconut:
In a food processor, grind all the ingredients together until you get a firm dough like modeling dough.
Take small paper cups or tartlets and put the dough in them, then spread it with your fingers to form a border.
Refrigerate.

Coconut cream:
In a saucepan, heat the coconut milk and grated coconut without boiling.
In a bowl, mix the egg yolk, cornstarch, and sugar with a whisk.
Add the warm coconut mixture to the previous mixture.
Put everything back in the saucepan and cook over medium heat for about 2 minutes.
Add the butter and emulsify with an immersion blender.
Let it cool for 30 minutes in the refrigerator, then pour it over the reserved tartlets.
Let it set in the refrigerator, ideally 24 hours.

Coconut crunch:
Preheat the oven to 350 F (180 C) and toast the coconut for about 10 minutes.
In a non-stick pan, caramelize the sugar and water over medium heat, then add the toasted coconut and mix with a wooden spoon for 3 to 4 minutes.
Spread the mixture on a plate or a parchment paper and let it cool to room temperature.
Crush the crunch with your fingers and spread it over the top of the tartlets.