How to Make Smooth Buttercream Frosting

In this baking tutorial post, I will share with you my top 10 favorite tips on how to make smooth buttercream frosting for cakes and cupcakes.

Making Smooth Buttercream Frosting

Having smooth buttercream frosting is a great way to make your cakes and cupcakes look phenomenal. Whether you are piping swirls of frosting onto cupcakes or smoothing buttercream onto a cake, air bubbles are the enemy!

Through lots of trial and error, I have found some simple tips and tricks to making super smooth buttercream frosting.

To test out these tips, I recommend trying them out with my vanilla American buttercream recipe. It tastes amazing, is easy to make, and is the best vanilla buttercream frosting to practice with.

So no gatekeeping here! Here are my top 10 tips on how to make smooth buttercream frosting.

1. Use room temperature butter

The first step to making perfectly smooth and silky buttercream frosting is to start off with room temperature unsalted butter. Room temperature butter is not too firm and not too soft. Having the right butter temperature allows the butter to whip up well and be super creamy.

The best way to test and see if the butter is the right temperature is to press it with a clean finger. The butter should indent with some resistance.

If the butter is too cold, you won’t be able to press into it with your finger. If the butter is too soft, it will feel mushy and appear greasy.

2. Whip the butter before adding any other ingredients

The next step to making smooth buttercream is to whip the butter for about 5 minutes on medium speed before adding any additional ingredients.

Whipping the butter alone allows the butter to become light, pale and fluffy. It is important to incorporate some air into the butter at this stage of the process to make a smooth and creamy, pale white buttercream frosting. The butter will change from a yellow color to a very pale yellow color/creamy white color.

This step is key to getting the right consistency at the end of making the frosting.

3. Make sure the powdered sugar is not lumpy

For super smooth buttercream, you want to use powdered sugar that is very fine and not lumpy. Lumpy powdered sugar instantly adds grit to the frosting.

If the powdered sugar you are using appears to be lumpy, I recommend sifting it before you add it to the whipped butter. You can run the powdered sugar through a fine mesh sieve/strainer, or you can use a sifter.

It is also good to note that different brands of powdered sugar can have different textures. Some are finer than others. Test out different brands of powdered sugar to find your favorite and what works best in your buttercream.

4. Don’t skip out on the heavy cream

Adding heavy cream or heavy whipping cream to the buttercream is a great way to smooth out the buttercream even more. The heavy cream helps to dissolve a bit of the powdered sugar and helps all of the ingredients come together. Adding heavy cream helps to create a super smooth and silky buttercream frosting.

Can you add milk or half-and-half? Absolutely. However, I have personally found that heavy cream creates the silkiest texture due to the high fat content.

5. Scrape the bowl

Perhaps this one is obvious, but scraping the sides and bottom of the bowl is a key step in making a super smooth buttercream. Ingredients can often get stuck on the sides and bottom of the bowl where the paddle or beaters can touch it. This can create pockets of powdered sugar or butter that are not well incorporated into the frosting.

I recommend scraping the sides and bottom of the bowl in between each step of the buttercream making process to ensure that everything is well combined and smooth.

6. Make the buttercream frosting with a paddle attachment

Another key to making silky smooth buttercream frosting is to use a paddle attachment. The paddle attachment whips the buttercream without adding too much air to the frosting. If you are making American buttercream frosting (butter, powdered sugar, salt, vanilla extract, and heavy cream), I recommend using the paddle attachment.

However, there are some exceptions to this rule.

When making emulsified buttercreams (ex. Swiss meringue, Italian meringue, Russian buttercream, ermine buttercream), you should make the frosting with a whisk attachment to help with the emulsification process in order to make the buttercream fluffy, thick and creamy.

For these buttercreams, I recommend following the instructions by starting off with the whisk attachment and then following tip #7!

7. Mix the frosting on low speed with a paddle attachment

Any easy way to remove excess air bubbles and smooth out the buttercream frosting is to mix the buttercream with a stand mixer fitted with a paddle attachment on the lowest speed for several minutes. The combination of the paddle attachment and low speed helps push excess air out of the buttercream to make it smooth.

If you are making an emulsified buttercream frosting recipe such as Swiss meringue buttercream or Russian buttercream that requires a whisk attachment, you can switch over to the paddle attachment at the very end to smooth it out.

The time it takes to remove the air bubbles can vary depending upon the type of frosting, but generally, 5 to 10 minutes will do.

8. Mix the buttercream by hand with a rubber spatula

Another great way to remove air bubbles from buttercream is to mix the buttercream by hand with a rubber spatula.

After you make the buttercream, use a rubber spatula to mix the frosting, pushing out the air pockets, to get the perfect texture and consistency. This method does take a bit of muscle, but it is definitely worth it.

If the buttercream sits for a period of time (ex. In between crumb coating a cake and the final layer of frosting), be sure to mix it by hand before frosting. As the buttercream sits, air bubbles will form, so mixing it before using is very important.

9. Melt a small portion of the buttercream

This is one of my favorite tips for making smooth buttercream frosting. It’s almost like magic!

I especially like to use this trick when I have made buttercream ahead of time, stored it in the refrigerator, and need to rewhip it to use for a cake or cupcakes, but you can also use it when you are making the frosting the day you plan on using it.

After you are done making the buttercream, remove about 1/2 cup of the frosting and put it in a microwave-safe bowl. Heat the buttercream in the microwave for 10 to 15 seconds until the buttercream is melted. Pour the melted buttercream into the big batch of frosting, and mix on low speed for a few minutes until silky smooth and creamy.

10. Get rid of air bubbles when they form in the buttercream

Even when you have the smoothest buttercream ever, as it sits, inevitably, air bubbles will start to form in the frosting. Here are some ways to address the air bubble problem.

Don’t let a piping bag sit for a long period of time. Fill your piping bags immediately before piping the buttercream onto cakes and cupcakes.

After you have added a crumb coat to your cake and are chilling it in the fridge, mix the frosting well before adding the final layer of frosting onto the cake.

Although air bubbles are the enemy, it is impossible to get rid of them all. In other words, it is hard to get perfection here. Just remember, even if your buttercream is not perfectly smooth, it will still taste great! And in the end, that is what I feel matters the most.

I hope you found this post the be helpful and that your next batch of buttercream is silky smooth. Let me know if you have any other tips and tricks for making smooth buttercream frosting!