Macadamia Nut Macarons with Passionfruit White Chocolate Ganache

Macadamia Nut Macarons with Passionfruit White Chocolate Ganache
Macarons:
225g Powdered Sugar
100g Macadamia Flour
90g Almond Flour
25g Granulated sugar
90g Egg Whites
1 tsp meringue powder

1. Three days in advance, separate the egg whites. Cover with plastic wrap and leave at room temperature until you are ready to finish the cookies.
2. At least a day in advance, grind the nut flours and combine with powdered sugar. Sift these 4 times, regrinding any time you have leftover nuts in the sifter.
3. On baking day, preheat the oven to 200F. Prepare pans by lining them with parchment paper (I had 4 pans ready). Have a spray bottle with water handy. 
4. Prepare a pastry bag by standing it upright in a tall glass. Fold the edges over the sides of the glass. This will allow your free hands to spoon in the batter and hold the bowl without having to hold the bag too.
5. Pour the egg whites into a large bowl for mixing. Add the meringue powder.
6. Whip the egg whites to soft peaks.
7. Gently add the granulated sugar to the whites and continue mixing until you reach stiff peaks.
8. Sift a third of the nut flour mixture onto the meringue and fold to combine. Repeat until all of the flour is incorporated, but do not over-fold or you will lose volume. 
9. Immediately spoon the batter into the pastry bag, cut the tip of the bag (unless you're using a pastry tip) and gently pipe rounds onto the baking sheets. 
10. Allow the pans to rest on a level surface for 30 minutes. If you don't do this, you will not form 'feet' on the macarons.
11. After 30 minutes, place the sheets into the preheated oven and bake for 6 - 8 minutes. Watch them very carefully for browning or splitting, which they will do if they get too hot or the bake for too long.
12. Remove the pans from the oven and immediately lift the corner of the parchment and spritz water onto the pan, dropping the parchment back on to allow the paper to capture some steam. Repeat this for the remaining 3 corners of the paper.
13. As soon as you can gently remove the cookies from the pan, do so - and cool them on a baking rack. It may help to use an offset spatula to slide underneath the cookie and help it pop off the sheet.
14. As soon as the cookies are cool (probably 10 minutes), place them in an airtight container or a ziploc bag (pull out as much air as you can). Fill when ready.

Passionfruit White Chocolate Ganache:
1 c heavy cream
1/2 c passionfruit concentrate
1 c white chocolate, chopped

1. In a heavy-bottomed saucepan, combine the heavy cream and passionfruit concentrate and heat until scalding (do not allow it to burn the bottom of the pan).
2. Place the chopped chocolate in a bowl.
3. Pour the hot cream mixture over the chocolate and allow it to stand for 5 minutes without stirring.
4. After 5 minutes, begin stirring the mixture. The chocolate will melt into the cream mixture. If chunks of the chocolate remain, heat a little more cream and add it to the bowl.
5. When the chocolate is completely melted, cool the mixture to room temperature, cover and then chill in the fridge until firm.
6. When you're ready to use the ganache, remove it from the refrigerator and whip it quickly with an electric mixer. This will incorporate air and will soften the ganache.
7. Spoon it into a piping bag.

To assemble the macarons, pipe some ganache into the middle of a macaron cookie. Gently twist the top cookie onto the ganache to create a sandwich. It will take a few cookies before you get the proportions right, but make sure you don't press the ganache too hard onto the cookie base or you're likely to crush the bottom cookie.

A few helpful hints when making these cookies:

• You can run the granulated sugar through the food processor too. It will make it nice and powdery when you add it to the egg whites.
• This recipe indicates 5 egg whites, but when I cross-referenced the proportions against other recipes, I saw mention of 90g a number of times. I checked it against several other sites and recipes and decided I would go with the 90g measurement, no matter how many egg whites that was. 90g is only 3 egg whites for me - a big difference that might have changed how successful this was. 
• I added 1 tsp meringue powder to the egg whites before whipping. I don't know if this helped or hurt, but I saw it as a suggestion (along with the 3-day aging) and thought it would be good insurance. That said, the best thing was that the egg whites were absolutely at room temperature before I started mixing.
• No amount of sifting is too little.
• I did not slam the cookie sheets on the counter to flatten out the rounds. Why would I want to deflate them?
• The spray bottle really helped on those sheets with parchment. I made one sheet with silpat and everything stuck to it. And those cookies got too hot - they cracked before I took them out of the oven, even though another sheet (on parchment) was still in and remained uncracked.

Accompanying photos are below. Note that I do show some of the cookies that cracked, burned, and fell apart!