Once you’ve piped as many circles as you could, bang the trays against the counter a few times each.
To assemble the macarons transfer the ganache to a piping bag and pipe it on the bottom shells of the macarons.
Cream of tartar: Cream of tartar’s acidity helps the egg whites achieve their full volume potential, and makes them stable by helping hold the water particles and the air particles in place. I am making my Swiss method recipe but adding cream of tartar to it, because I frequently get asked about adding cream of tartar to this recipe. It made a sturdy meringue, with perfect peaks.
Vinegar: Before starting make sure to wipe down the bowls, whisks, silicone mats and everything you are going to use with vinegar, to avoid any grease particles of coming into contact with the meringue and batter.
Food coloring: Make sure to use gel food coloring, not liquid. I love Americolor. If you are a beginner macaron baker, I recommend going easy on the food coloring, as it can alter your batter a lot, and it can take extra mixing time, specially if you continue to add the food coloring as you do the macaronage. Please read more about macarons and food coloring here.
Macaron amount: it will vary greatly depending on how big you pipe the shells, and on how runny or thick the batter is.
Baking time/temperature: Baking time and temperature will vary according to your own oven. I recommend experimenting with your oven to find out the best time, temperature, position of the baking tray.
Oven thermometer: Make sure to have an oven thermometer to bake macarons. It’s one of the most important things about making macarons. Home ovens aren’t accurate at all at telling the temperature, and even a slight 5 degree difference can make or break your whole batch.
Tray rotation: Lots of bakers don’t have to rotate the trays 180 degrees in the oven every 5 minutes, but I do have to with my oven, or I will get lopsided macarons. Please adjust this according to your oven.
Macaron Tools: Please visit this post to check out all the tools I use to make macarons.
White Chocolate: Make sure to use good quality white chocolate, don’t use white chocolate chips, or candy melts. Use bar white chocolate appropriate for baking. Most chocolate chips bought at the store are not actually white chocolate. To be considered white chocolate, it must have at least 20% cocoa butter. I use Callebaut callets, they have 28% cocoa butter and I get them on Amazon, it’s my favorite chocolate for baking.
Tips for ganache: If you have issues with the white chocolate ganache, first make sure you are using good quality white chocolate, as mentioned before. Also here are a few things you can do, add 2 tbsp of butter to the ganache after incorporating the heavy cream. And if the ganache has separated, add some slightly warmed heavy cream by the tablespoon, and whisk until it comes back together.