Coconut Cupcakes: Preheat the oven to 170 degrees C. Line a muffin tray with patty cups.
Beat sugar and butter in a mixer on high until fluffy; about 8 minutes. Add half of the coconut milk and vanilla and blend. Sift together dry ingredients twice. In the mixer alternate the coconut milk and dry ingredients three times. Transfer batter into a large bowl and clean mixer bowl thoroughly.
Whip the six egg whites to a stiff peak. Fold it into the batter careful to keep the batter light. Transfer into patty cups bake in the preheated oven for 30 - 35 minutes.
Lemon Curd: Combine yolks, lemon juice, zest and sugar in a bowl then place it over a saucepan of simmering water. Do not let the bowl touch the simmering water. Use a rubber spatula to stir the mixture. Stir frequently until thick; about 15 minutes. Remove from heat and whisk in butter pieces one at a time. Strain the entire mixture into a bowl and cool with plastic wrap directly on the lemon curd. It will thicken even more as it cools.
Filling the Cupcakes: When the cupcakes and the curd are cool scoop out some of the cupcake using a measuring spoon. Make the hole big enough to hold a tablespoon of lemon curd. Fill the cupcakes with the curd so that it is at the same level as the cupcakes.
Meringue: Do this step last; after you have filled the cupcakes with curd. Combine the egg whites and sugar in a bowl over a simmering pot. Whisk and stir the eggs until the sugar has dissolved and the mixture doesn't feel grainy.
Whip the egg whites in your mixer on medium and then high when it starts to develop peaks; after about 4-6 minutes. Stop when the meringue is stiff and can hold a shape without melting into itself; about 8-10 minutes.
Use a piping bag and star tip to pipe rosettes on the cupcakes. Torch them with a creme brulee torch and top with toasted coconut. They can be refrigerated with the meringue on top for up to two days.