How to Fix Hollow Macarons

You finally made beautiful macarons with smooth tops and pretty feet. But when you break into them, they’re completely hollow inside!! Ugh, how I understand the frustration!!

Well, good news is that you’re in the right place!

As someone who had struggled with hollow macarons for couple of years (even with the best macaron recipe!), I totally understand how frustrating it can be. After many, many testing I finally cracked the code to fix hollow macarons.

Are macarons supposed to be hollow?

So, is it bad if macarons are hollow? The short answer is yes and no!

First, let me assure you, a small gap in macarons is not a big deal. As long as your macaron shells have smooth and sturdy tops, ruffled feet, and straight bottoms, a small gap between the top layer and chewy center and/or small airpockets are not a problem!

In the picture above, I would consider the green and pale blue macarons as a success! Once you fill these macarons with buttercream or ganache and mature them overnight, the shells will be full and no one will notice any hollowness.

That being said, hollow macarons become an issue if they are completely hollow in the center. In some cases, the tops are fragile and break with a gentle touch.

The main problem with this kind of macarons is that they will crumble as you bite into them even after filling and maturing them! And that’s no good.

Why are my macarons hollow?

Macarons turn out hollow for number of reasons. The most common culprits are:

• Weak meringue
• Over-mixed batter
• Improper piping technique
• Under-baked macarons

Now that we know what causes hollow shells, let’s talk about how to fix them!

How to fix hollow macarons

As mentioned above, many different things could cause hollow macarons. It’ll require some testing on your part to perfect your technique and achieve perfectly full macarons. And the following tips will help you to do just that!

TIP #1: whip your meringue low and slow

The key to the most stable French meringue is to whip it low and slow at a consistent speed from start to finish. This way your meringue will form small and uniform bubbles which leads to a strong and thick meringue.

In the last few years, I made a small change in my meringue technique. Instead of adding sugar in small amounts, I now combine the egg whites with all the sugar, cream of tartar and salt from the get-go. Then I set my KitchenAid stand mixer to speed 4 and let it whip into a nice and thick meringue.

Electric handheld mixer works great as well. Use the medium speed to whip the meringue.

TIP #2: Don’t Over-Mix the Batter

Over-mixed macaron batter could cause hollow macarons. Make sure the batter is just runny enough to flow into ribbon and melt back into the rest of the batter within 10 seconds, but still thick enough to hold its shape when piped.

Watch this short Instagram video on how I test if my macaron batter is ready.

TIP #3: Master PRoper Piping Technique

The proper piping technique plays an important role.

1. Hold your pastry bag with the macaron batter at 90° angle.
2. Squeeze the batter from the top at a consistent pressure.
3. Pipe the batter until desired size without swirling around.

Watching the piping technique in action

TIP #4: Use a Small Piping Tip

To make perfectly round circles, I highly recommend using a round piping tip. I used to use Wilton 1A in the past.

However, when I switched to a slightly smaller tip, my macaron shells started to come out 100% full without any small gaps. I can’t exactly explain the science behind it, but my guess is that smaller tip allows me to pipe the batter denser.

Wilton 2A piping tip is my go-to, and sometimes I even use Wilton 12.

TIP #5: Avoid Under-baking Macarons

From seeing many, many hollow macarons from my followers on Instagram, I can confidently say that the most common reason for hollow macaron shells is under-baked macarons!

When macarons are under-baked, they collapse inside while cooling, leaving the macarons hollow inside.

It’s an easy fix! Here’s how to prevent under-baked macarons:

• Make sure your oven is not running hot. If the oven is too hot, the macarons start browning on the outside while they’re not fully baked and set inside. TIP: Use an oven thermometer to double check the accuracy of your oven and ensure your oven is not running hotter than it indicates.
• Be sure to preheat your oven sufficiently before baking macarons. I recommend to turn on your oven for at least 30 minutes. In the first 30 minutes, your oven temperature will fluctuate the most.

Bonus Tips

1. Use storebought powdered sugar, because commercial powdered sugar contains cornstarch. And cornstarch helps to make meaty macarons. However, I do NOT recommend adding constarch to the meringue or dry ingredients.
2. And lastly, make sure to mature your macarons. If your macarons have just a little bit of gap at the top, don’t fret. Once you fill the macarons and mature them in the fridge for about 24 hours, they’ll magically fill up.

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