For the passion fruit curd:

1. In a bowl, beat yolks and sugar for 1 minute. Add passion fruit and reserve.
2. Melt butter in a medium saucepan over low heat. Before it boils, add yolk mixture and cook over medium/low heat, stirring constantly, until the mix thickens, but without letting it boil.
3. Pour into sterilized jars if you plan to keep it for a few weeks, and not use it within the next 5 days.
4. Keep refrigerated.

For the coconut cupcakes:

1. Preheat oven at 350ºF/180°C.
2. Fill a muffin tin with 12 paper liners.
3. Sift flour, baking powder and salt.
4. In a large bowl, beat butter for 1 minute. Gradually add sugar, beating constantly at medium/high speed.
5. Add eggs, one at a time, beating well after each one. Add coconut and vanilla and mix to combine.
6. Add the dry ingredients in 3 parts, alternating with the buttermilk in 2 parts. Don’t over mix at this point, or the cupcakes will be tough.
7. Fill paper liners to ¾ of their capacity, and bake for about 25 minutes, until golden, springy to the touch and a tester comes out clean.
8. Let cool completely on a wire rack.
9. Scoop the top center of each cupcake. I use OXO One-size melon baller, which makes it super easy. But you can use a spoon or small paring knife. 
10.  Fill with the curd carefully.
11. Pipe or spoon the frosting on top and top with toasted coconut to decorate.

For the cream cheese frosting:

1. Beat cream cheese and butter until very smooth.
2. Add sugar, gradually, until you have a thick batter that can be piped.
3. Keep covered, in the fridge.