How to Thicken Homemade Frosting - Kickass Baker (2024)

Achieving the right consistency to your frosting is important. This will ensure the frosting is easy to pipe and holds its shape when piped. If the frosting is too soft, it will not hold its shape and will slide off your cupcakes or cake layers.

Frosting that is too thin can make it difficult to pipe with a piping bag or use to fill a cake, leaving you with a lackluster-looking cake. Luckily, there are tips and tricks to save your homemade frosting and achieve the right consistency!

Interested in making your own homemade frosting? Try my Dark Chocolate Buttercream, Oreo Frosting, and Salted Caramel Frosting recipes.

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What causes thin frosting?

Frosting is an essential finishing touch to any cake or cupcake. And it is surprisingly easy to make your own at home. This allows you to customize the flavor and texture so that you can make the perfect frosting for your dessert.

On the other hand, frosting that is too thick or stiff will be difficult to pipe or spread. Thinning out frosting is pretty simple, though! It just requires adding a bit more liquid.

But what happens if you find yourself with frosting that is too thin? How do you thicken homemade frosting to achieve the right texture for piping, spreading or using as a filling?

There are a few different causes of thin frosting. It is helpful to understand where the process went wrong to figure out how to fix it.

First, the issue may be that your kitchen is too warm making for warm frosting that is loose and runny. Because frosting is primarily comprised of oil or fat, it can easily become runny and thin at higher temperatures.

Temperature of butter can affect frosting consistency

Similarly, if your frosting recipe contains butter and the butter was too warm when it was added, this can result in a runny buttercream.

The temperature of your butter is one of the keys to success in making smooth, delicious frosting. I recommend removing it from the fridge at least an hour or more before you begin making the frosting.

I like to leave my butter on the counter overnight. This ensures you will not have cold butter, which tends to leave chunks of butter throughout the frosting.

If the temperature of your kitchen is very warm though, you may end up with melted butter, which will yield soupy and/or greasy frosting. You want butter that is soft but not melted or greasy.

If your frosting is not thin due to the heat, it could be a result of too much liquid. Double-check your recipe to see how much milk is called for in the ingredients. If you accidentally added too much, this could be why your frosting is thin. Luckily, there are some easy fixes!

Methods of fixing thin frosting

Whatever the cause of your runny frosting, you have a couple of options to fix it and achieve the thick and creamy frosting you are looking for. We will discuss below the common causes of runny icing and different methods of saving your hard work.

Refrigerate

If you suspect that your frosting has gone thin because it is too warm, the best way to fix it is with some time in the refrigerator.

If your frosting has been at room temperature, or your kitchen is warm from the oven, simply cover the top of the mixing bowl with plastic wrap, and place it in the fridge for 30 minutes.

When you remove the frosting from the fridge, beat it with a hand mixer or stand mixer until it has a smooth consistency. This is an easy way to fix a whipped cream frosting, or one with a butter base, as those are typically the frosting types most impacted by a hot kitchen.

Add More Dry Thickening Agent

The temperature of your icing may not be the cause of it being runny. It may be that there is too much liquid in your mixture or not enough dry ingredients.

Liquid ingredients may include whole milk, nondairy milk, heavy cream, vanilla extract or other extracts. A great way to fix this is by adding more thickening agent.

Powdered Sugar

Most frostings are made with powdered sugar (otherwise known as confectioners' sugar or icing sugar), which contains cornstarch to prevent it from caking. Adding more powdered sugar can be an effective way and the easiest way of absorbing too much liquid to achieve thicker frosting.

Be careful when doing this though, as adding too much additional confectioners' sugar to the runny icing can alter the taste of your frosting, making it too sweet. Add 1 to 2 tablespoons of milk at a time, making sure to whisk or mix with an electric mixer in between each tablespoon to check the consistency.

If you accidentally make the frosting too thick, add a small amount of milk (or a dairy-free alternative like coconut milk). The most important thing is to move slowly to avoid this so you do not get stuck in a cycle of trying to get the perfect texture.

More Dry Thickening Agents to help thicken homemade frosting

Cocoa Powder

If you are making a chocolate frosting, adding more cocoa powder is a great option for thickening it.

The technique is basically the same as if you were thickening with powdered sugar, but you want to use a smaller quantity of cocoa powder than icing sugar. Try adding just 1 to 2 teaspoon at a time. Any more and it may become too thick or bitter.

Flour

Flour can only be used for heated frostings, as raw flour must be cooked. But if you will be warming your frosting on the stovetop, you can add 1-3 teaspoon of flour to give it a thicker consistency.

Be sure to remove the frosting from the heat as soon as it has reached your desired consistency so that it does not separate. This means the fat (butter or oil) pools at top and the flour settles to the bottom. Instead, the frosting should be even in consistency with the fat and flour mixed well together.

Meringue Powder

Meringue powder is another dry ingredient that can help you make your frosting nice and fluffy. Mix in about 1 tablespoon of meringue powder per cup of frosting being careful to work slowly. A

Adding too much meringue powder may decrease the sweetness or flavor of your frosting. If you need to make your frosting sweeter after adding meringue powder, you can add a dash of sugar.

Add Moist Thickening Agent

​Cream Cheese

If you need to thicken your frosting but are worried about it becoming too sweet, you can add cream cheese to balance the runnyness and achieve the perfect consistency.

This method is most helpful is you are already making a cream cheese frosting, but can also be used to add tanginess to other types of frostings.

Your frosting will mix best if the cream cheese is already softened or at room temperature. Add just 1 oz at a time and mix with a stand mixer or hand mixer on medium speed in between additions.

You do not want to add too much at once, or you risk making the texture too thick or adding too much tanginess to your frosting.

Heavy Cream

Making a frosting that is sturdy enough to beat with an electric mixer and that can be chilled? Try thickening it with a bit of heavy whipping cream.

You can add up to ¼ cup of heavy cream, depending on how much you need to thicken it. Then whip the frosting until it fluffs up.

Heavy cream also works if the recipe instructs you to heat the frosting. Add the heavy cream on low heat on the stovetop, and the heavy whipping cream will reduce, helping the frosting to thicken.

Peanut Butter

Making peanut butter frosting? Simply add more of this ingredient to thicken the frosting. Like the other thickeners, start with 1-2 tablespoons more and add more as needed, making sure to mix well in between additions to check the consistency.

How to tell if your frosting is the right consistency

There's a quick trick you can use to tell if your frosting is the right consistency. I learned this from Chelsweets, the cake queen!

After you have finished mixing the frosting, dip a rubber spatula straight into the middle of the frosting and pull it straight out. Hold the spatula right side up. The frosting should create a small curl at the tip that's coming off the spatula.

If the frosting is sticking straight up without that curl, it's a bit too stiff and needs a bit more liquid such as milk, cream, or extract.

If the frosting flops over and doesn't have that curl, it's too loose and needs a bit more dry thickening agent such as powedered sugar, cocoa powder, flour or meringue powder.

Homemade frosting recipes