Ensure your cake pan is clean. Temper the chocolate and add to as many cavities, as the amount of chocolate allows (you may need to do it in two batches reusing the drained chocolate from the first batch). Tap the pan lightly to remove any air bubbles. Invert the pan to drain chocolate, scrape any excess and allow to set. Chill.
Melt chocolate and cocoa butter in a bain-marie to 40 ºC. Use a spatula to mix until smooth and fully combined. Allow to cool down to 35ºC. Transfer the chocolate spray to a good quality airbrush with a compressor and spray a thin coat on the chilled pots. Allow to dry and set aside.
Make the curd:
Fill a heavy-duty pot or heat-proof container with warm tap water. Attach the immersion cooker and set the temperature to 73.9ºC/165ºF. Cover to speed up heating.
Combine all the ingredients, except the zest, using a hand whisk, immersion blender or blender. Pour the mixture into a sous vide safe bag or jars, add the zest and seal partially and add the bag to the heated water bath using the displacement method. If using jars, screw the cap on finger-tip tight, or attach cap and clips. Cook for 45 minutes, up to 1 hour.ORSimply add all the ingredients, including zest, to a sous vide safe bag, seal and cook, as above. You will need to agitate the bag a couple times throughout the cook and blend post cook, in this scenario.
Prepare an ice bath close to the end of the cook. Once cooked, remove the curd from the water bath and shake the contents. If you prefer a smoother texture, strain off the zest. Place the cooked curd in the prepared ice bath to cool down for about 20 minutes. Transfer to an airtight container and refrigerate for at least 6 hours. Best when consumed within 2 weeks.
Stove-top Option:If you don't cook sous vide, add all the ingredients to a medium saucepan and cook the mixture, while stirring, over medium heat until it thickens. Transfer to a clean jar, allow to cool, then seal and refrigerate for up to 2 weeks.
Bake the cake:
Preheat oven to 350ºGrease pan and place on a cookie sheet. Set aside.
Sift all the dry ingredients into a large bowl and make a well in the centre.
In a separate bowl, lightly whisk together all the wet ingredients, except coffee.
Add the wet mixture to the dry ingredients and use a whisk to stir the batter. It will be thick.
Add the warm coffee and continue to stir with the whisk until fully combined.
Divide the batter evenly into prepared cavities of the cake pan.
Bake for 25-30 minutes on the cookie sheet on the middle rack of the oven. Rotate cookie sheet halfway
through baking.
Test for doneness, remove from oven and allow to cool for about 15 minutes on a cooling rack.
Place a cooling rack over pan and invert to release cakes. Allow to cool completely.
Whip the cream:
Chill a stainless steel bowl and whisks. Add the chilled coconut cream to the chilled bowl along with the sugar and stabilizer, if using. Whip to soft peaks then add the passion fruit puree while whipping. Whip to stiff peaks, cover and chill until ready to use.