Why isn't my icing hardening?

If your frosting isn't thickening, it's usually because the fat (butter/cream cheese) is too warm or you've added too much liquid; the quickest fixes are chilling the bowl in the fridge and re-whipping, or gradually beating in more powdered sugar or cornstarch until it thickens. For buttercreams, chill the mixture, then whip again; for cream cheese frosting, add cornstarch or more powdered sugar slowly.

Why won't my icing set hard?

The icing needs to be exposed to the air to dry. This usually takes about overnight (approximately 8 hours).

How do I get my icing to harden?

It will take 12-24 hours for the icing to harden, depending on the thickness of the frosting. For best results, set decorated cookies on a baking sheet in a single layer and leave overnight. Before stacking, wrapping, or storing make sure the icing is hard throughout.

Why won't my icing stiffen?

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.

Why is icing not setting?

Your icing might be too warm or have too much butter. Try refrigerating it for 10-15 minutes to firm up. Alternatively, add a small amount of powdered sugar to balance the ratio. If still issues, consider restarting with adjusted proportions.

Common Royal Icing Mistakes - how to troubleshoot common problems with royal icing

How to fix icing that's too runny?

To fix runny icing, add more dry ingredients like powdered sugar (1-2 tbsp at a time) or a thickener like cornstarch, mixing well after each addition until it thickens; alternatively, chill buttercreams if the fat is too warm, or incorporate other dry ingredients like cocoa powder or peanut butter for flavored frostings. 

Why does my icing stay soft?

This could be because the butter was too soft or you added too much milk if it is buttercream frosting or it could be that you have overbeaten it if you're making cream cheese frosting. Also, a hot kitchen can make frostings go runny, so be mindful of the temperature.

Can you overbeat buttercream?

Yes, this is absolutely correct. The longer you beat, the more air you incorporate in your buttercream, thus, it will have lots of holes or air-pockets, it will also make the colour lighter. If you will use your buttercream primarily for filling or maybe as simple swirls, then this is ok.

Will runny icing set in the fridge?

Some tips: if your frosting starts getting runny, pop it in the fridge for a few hours and whip it back up.

Can I put icing in the fridge to harden?

Yes, most icings, especially buttercream, will harden in the fridge because the butter solidifies, but they usually soften back up at room temperature; royal icing hardens to a candy-like finish, while buttercream gets firm but can be re-whipped to fluffiness after warming up. 

Does icing harden faster in the fridge?

As mentioned above, royal icing needs to be exposed to air to be able to dry completely. By putting wet royal icing in the fridge you are not only preventing the icing from actually drying, but the humid environment will also likely make the colors bleed.

How do I harden icing?

Use a hairdryer! Make sure the hair dryer is on the cool setting, otherwise you'll just cause your icing to melt. This method isn't great for large or dense pieces, but it is great for drying up small pieces of fondant.

How long until icing hardens?

Icing setting time varies, but generally, a thin crust forms in 15-30 minutes, while full hardening can take 6-24 hours, depending heavily on the icing type (royal vs. glaze), thickness, and humidity. Royal icing needs 6-8 hours for a firm crust, but 12-24 hours to fully harden for stacking. Thicker icings or high humidity slow drying. 

How to make icing harden faster?

To harden icing fast, use cool air from a fan or hairdryer, a food dehydrator on a low setting, or a cooled oven with the door cracked, which are all effective for royal icing; for fondant, use a fan or a low-heat lamp to speed up drying time on a hard, flat surface. Adding a bit of corn syrup or meringue powder to your recipe can also help it set quicker. 

How do I firm up my buttercream?

To stiffen buttercream, chill it in the fridge for 10-15 minutes and remix, add more sifted powdered sugar in small batches (2-3 tbsp at a time), or incorporate a small amount (1 tsp) of cornstarch or meringue powder for stability without extra sweetness. For a firmer frosting, especially in heat, consider adding milk powder or even melted white chocolate. 

How to fix wet icing?

To fix runny icing, add more dry ingredients like powdered sugar (1-2 tbsp at a time) or a thickener like cornstarch, mixing well after each addition until it thickens; alternatively, chill buttercreams if the fat is too warm, or incorporate other dry ingredients like cocoa powder or peanut butter for flavored frostings. 

What are 5 mistakes to avoid when making butter icing?

To avoid buttercream mistakes, use room-temperature butter, sift powdered sugar to prevent lumps, don't overmix (especially after adding sugar), add liquids gradually for consistency, and use gel colors instead of liquid to keep it from getting runny. Patience is key, as proper creaming takes time, but overmixing can cause a curdled texture or air bubbles. 

What to do if my icing is too soft?

Add all of the frosting ingredients to a bowl EXCEPT for the powdered sugar. One tablespoon at a time, add in the powdered sugar, and mix. Keep adding powdered sugar until the glaze is thick and starts to hold its shape. Adjust with a small amount of water or milk if necessary until desired consistency is reached.

How do I stiffen up buttercream?

To stiffen buttercream, chill it in the fridge for 10-15 minutes and remix, add more sifted powdered sugar in small batches (2-3 tbsp at a time), or incorporate a small amount (1 tsp) of cornstarch or meringue powder for stability without extra sweetness. For a firmer frosting, especially in heat, consider adding milk powder or even melted white chocolate. 

Why is my buttercream not stiff enough?

By bringing down the temperature, the frosting should tighten up immediately. This is a great trick for buttercream frosting that may have been overmixed or made in a warm kitchen. If this doesn't seem to do the trick, try adding sifted powdered sugar, a few tablespoons at a time.

Why spray water on cake before frosting?

A cake soak is liquid that is brushed directly onto each cake layer after baking but before frosting and filling. The liquid “soaks” into the cake, adding more moisture to prevent the cake from drying out and infusing additional flavor and/or sweetness. A variety of liquids can be used as a cake soak.

How to firm up icing?

Method 1: Add More Powdered Sugar

This is the easiest fix for most icing problems. Start with just one tablespoon of sifted powdered sugar at a time. Mix it in completely, then check your consistency. Repeat this until you get the thickness you want.

Why is my icing not thickening?

Too Much Liquid = Add More Dry Ingredients

To thicken frosting that contains too much liquid, we'll need to balance out all the liquid by adding more dry ingredient(s). The most common solution is simply to add more powdered sugar.

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