One "o" or two? What does it mean? Why are their names so annoyingly similar? I got tired of listening to the debate so I decided to put it to rest/make it more confusing. This recipe is a bit of an undertaking (as macaron often are), but if you love coconut as much as I, its well worth it. I generally make the filling with a Valrhona product called "Caramelia" which is, exactly what it sounds like, caramel. Since white chocolate is much more easily sourced (and less expensive), I substituted it here. —PieceOfLayerCake
To make the macaron shells: Preheat the oven to 300F/150C. If your oven has a convection feature, now is the time to use it. Line 1 sheet pan with parchment paper and spread the coconut out on another. Toast the coconut until just lightly golden, about 5 minutes, tossing once during cooking. Transfer to a plate to cool completely. Allow the sheet pan to cool and line with parchment paper. Install a pastry bag (reusable or disposable) with a large round tip and set aside.
Combine the almond meal and confectioners' sugar in a food processor and pulse 8 - 10 times, or until well combined. Dump into a large bowl. I find that wide, shallow bowls work best for this step. Add 60 g. of the egg whites to the mixture and, using a spatula or bowl scraper, combine into a thick paste. Set aside. Combine the remaining egg whites and egg white powder in the bowl of stand mixer and affix it with a whisk attachment. Begin to mix on the lowest speed.
Combine the water and granulated sugar in a saucepan and begin cooking over medium heat. Clip a candy thermometer on the side of the pan and continue cooking until the mixture reaches 220F/104C. Increase the speed of the mixer to medium. When the sugar reaches 244F/117C, remove it from the heat. Increase the mixer speed to high and, when the eggs reach firm peaks, begin to stream the sugar syrup down the side of the bowl. Try not to hit the whisk with the syrup. Continue mixing for a couple minutes, or until the meringue holds stiff, glossy peaks.
Remove the meringue from the mixer and, using the bowl scraper/spatula, vigorously mix ⅓ of the meringue into the almond paste until well incorporated. Add the remaining meringue in 2 increments, folding each gently until incorporated. Continue folding the mixture 3 or 4 times, until the batter falls from the spatula in thick ribbons.
Transfer the mixture to the prepared pastry bag and pipe the batter in half-dollar sized rounds (the size isn't nearly as important as the uniformity), allowing ½" space in between each. Lift each sheet pan and firmly rap it on the counter 3 - 4 times, settling the texture of the macaron. If prominent peaks remain, use a damp finger to *gently* smooth them out. If small imperfections are visible, don't fret. Take pinches of the toasted coconut and sprinkle half of the shells with about ¼ t. (use what you need, but leave half of the amount for the filling). Allow the shells to rest for 20 - 30 min on the counter.
Bake the shells for 12 - 15 minutes or until the shells don't move when lightly poked. Rotate the pans halfway through baking, especially if your oven is known for uneven baking, and pull the shells before they take on any color. If your oven doesn't have a convection feature, a fun trick I learned is to prop the oven open with a wooden spoon to allow steam to escape. Allow the shells to cool completely on the sheet pans.
To make the filling: Place the white chocolate in a large bowl. Heat the cream over medium heat, stirring frequently, until it just begins to bubble along the side. Immediately pour the cream into the chocolate and tap the bowl on the counter lightly to settle everything in. Allow to stand for a minute or two. Stir gently to combine the mixture into a glossy ganache. Add in 225 g. of the toasted coconut and fold to combine. Set aside and allow to cool to room temperature.
When everything is cool, flip over the coconut-less shells and spoon about ½ t. of the filling on top. Cover with a coconut-topped shell and press lightly to adhere. Eat immediately or store in an airtight container, in the refrigerator, for up to 3 days.