Overall, I really like the look of this book and purchased six of them, one for myself and five others for friends. But, for a book that is dedicated solely to the creation of the macaron, the French Meringue recipe will not yield successful macarons. After many many batches attempting to recreate the results shown in the book, I finally went in search of help on the internet and discovered this site: [...].
Helen Dujardin is 100% french, and in my opinion the US-based macaron guru. With her assistance, I have been able to correct the French Meringue recipe in I Love Macarons. There is a great deal of essential information missing from the book. For example, the amount of egg white needed is 90 gr, definitely DO NOT use three large eggs as even medium eggs will yield more white than needed. And, the eggs must first be aged. To age them, they need to be out of their shells, separated from the yolks and left to stand uncovered for a couple of days at room temperature in the coolest part of your kitchen. (To understand this process better and learn a work around, read Helen DuJardin's article Demystifying Macarons found on the internet.) Using non-aged eggs will cause the pied or foot of your macarons to spread. The pied should not extend beyond the shell.
Secondly, the information in the book on confectioner's sugar is confusing. For instance, the book says not to use confectioner's sugar containing cornstarch (cornstarch-free sugar is not available in the US as far as I can tell). However, the product sample pictured in the book, by Woodstock Farms, actually does contain cornstarch. I tried making my own cornstarch-free confectioner's sugar by whirling it around in my food processor until it was a fine dust, but this yielded very unsatisfactory results in the form of dull, cracked macarons with no pied. What I learned from Helen DuJardin, is that it is okay to use confectioner's sugar with cornstarch, but stay away from the discount brands as they may contain more cornstarch than sugar. The recipe in the book calls for 1 1/2 cups of confectioner's sugar and that should be increased to approximately 1 3/4 cup or 200 gr.
The amount of granulated sugar called for in the book is 5 tablespoons, however, I followed Helen DuJardin's recipe and used 2 tablespoons, and this is where the superfine sugar I made in my food processor came in handy and I used this rather than granulated sugar in my meringue.
The recipe in the book calls for 2/3 cup ground almond flour, way less than what is actually required. Use a full, firmly-packed cup or 110 gr. I purchased a five-pound bag on the internet from Honeyville but after reading Helen DuJardin's article, I will use fresh blanched almonds in the future as the pre-ground almond flour tends to be dry and will not yield optimal results. Blanched (without the dark skin) almonds will give you a macaron without the little specks, but either with or without skin will work.
From the standpoint of technique, and in addition to an accurate receipe, making macarons is all about the technique. Unfortunatley, I also found some problems with the techniques as described in the book. For example, the meringue should be whipped (on medium-high speed) just to the point where it will not slide out of the mixer bowl, reaching a medium stiff texture, or it will be too dry. The book says to beat on high until the meringue is stiff, firm and glossy, which may take it too far.
The macaronage technique (blending the meringue with the almonds and sugar) in the book is guaranteed to overwork your batter. What I found most helpful is Helen DuJardin's instruction that the whole process should take no more than 50 strokes. Too many strokes equals overworked batter and will give you thin batter that will not hold up once piped onto the cookie sheet. And, as an amateur patissier, it is important to note that while you do not want to overwork your batter, you do not have to worry about deflating the meringue as with other recipes.
As far as using two baking sheets is concerned, I found that when using a good quality baking sheet, lined with a Silpat or parchment paper,(a good recipe and proper technique), it is not necessary to use double baking pans and this actually kept my macarons from completely cooking on the bottoms, making them sticky and difficult to remove. As for cooking time, I think you will need to work with that a bit on your individual ovens. 280 degrees Fahrenheit for 15 - 18 minutes is what Helen Dujardin recommends.
I also had a problem with the butter cream making technique. When making the sugar syrup component, four minutes in the microwave is far too much time and cooking times can vary from one microwave to another. This is something better accomplished with a thermometer and getting the sugar to a temperature of approximately 235 to 240 degrees Fahrenheit.
In defense of Hisako Ogita, the author of I Love Macarons, I suspect that someone somewhere in the book publishing process tampered with her recipes, or perhaps they were corrupted in translation. She looks as if she genuinely does love macarons and is obviously getting successful results. In all my research, I did discover that professional patissiers prefer the Italian Meringue recipe over the French for consistent results (perhaps that is what Hisako used). I haven't gotten that far in I Love Macarons as of yet. The Italian recipe does require a little more technique expertise, but I think mastering the French one will prepare me for that eventuality.
Good Luck!