Every baker has that moment where it comes time to taste your wonderful macaron creation, and that first bite is nothing but air. It is so frustrating right? All that hard work, patience, and following the recipe exactly and yet they still don't come out right. So what gives??
After having had this experience many, many times, I really tried to take the time to examine each step, and what I noticed about the batter, ingredients etc. If my macarons came out perfectly, I would try to remember the differences between that batch compared to when they were hollow.
Listed below are some characteristics I noticed that will help guide you to a more perfect batch :)
Tip 1: Make sure you do NOT overwhip! It is so important to watch the meringue closely. If it means to keep starting and stopping, it is okay! It is better to keep checking than to overwhip. Macarons get the reputation of being an meringue "air-like" cookie, but from my experience, the less air you have the better!
Tip 2: Much like Tip #1, it is actually VERY important to knock as much air out of the batter without making the batter too runny. I had always learned that the meringue/batter is very gentle, but you really need to knock the air out as much as you can.
As the picture below, these air bubbles will ruin your cookies. The more air bubbles/ripples, the more likely you won't be able to get them all out when rapping the sheets on the counter. I know this might not be the "technical" terminology, but I have made batters with these air bubbles and more often than not they come out hollow.
Sometimes bakers might be able to get the air bubbles out by just folding, but I have always had to run the batter along the side of the bowl. I will drag the batter along the sides, and then scoop it back towards the center to check for consistency.
You should keep going till your batter and consistency looks like below:
As pictured above, the batter is smooth, shiny and very little air bubbles to be seen.
Tip #3: Make sure there is no extra air in your piping bag! A few times I have been piping, and there will be a big burst of air that spurts the batter everywhere! Hidden air bubbles in your piping bag will only make it more likely for your macarons to burst in the oven. To get rid of air in your piping bag, use a flat icing scraper to squish the batter towards the piping head to make sure that all extra air is removed.
These are a few tips I have for now, but will continue to add more as I continue to learn! Feel free to share any of your tips and tricks for no hollow macarons :)