Preheat the oven to 350 degrees F. Mix the chocolate cookie crumbs with the melted vegan butter, then firmly press the mixture across the bottom and sides of a 9-inch tart pan.
Bake the crust for 9 minutes. Set it aside to cool completely while preparing the caramel.
Combine the brown sugar, coconut cream, and vegan butter in a saucepan. Bring to a gentle boil over medium heat, stirring regularly, then cook for 5 minutes until glossy and slightly thickened.
Remove the caramel from the heat and stir in the vanilla and sea salt. Cool for 10 minutes, pour it into the crust, and refrigerate for 45 minutes.
Place the dark chocolate in a heatproof bowl. Heat the coconut cream until steaming, pour it over the chocolate, and leave it undisturbed for 3 minutes.
Stir the ganache until smooth, then mix in the vanilla. Pour it over the chilled caramel and spread it into an even layer.
Sprinkle the tart with flaky sea salt and refrigerate for at least 2 hours, or until firm. Let it stand at room temperature for 10 minutes before serving.
