Everything You Need to Know to Make Great Marshmallows

There’s something completely unreal about the transformation of sugar to marshmallow. You begin with sugar in its solid form of tiny granules, you heat it into liquid syrup, and you whip that syrup until it’s aerated. They’re solid enough to stay solid even when slightly heated, but extended heat makes them melty and oozy, all over again. Magic!

The good news is it takes no magic powers to make marshmallows.

Before we get to the recipe, let’s break it down:
1. What exactly is a marshmallow?
2. Play it safe.
3. Ready your ingredients.
4. Make friends with nonstick spray.
5. Prep your equipment.
6. Ready the pastry brush.
7. Bloom the gelatin.
8. Cook the sugar.
9. Whip the sugar.
10. The first shaping.
11. The second shaping.
12. Storing.

What exactly is marshmallow?

Marshmallow is an aerated confection made by cooking sugar into a syrup, then whipping it to stiff peaks. The mixture is set with gelatin, which gives it its signature chewy yet pillow-y texture.

Marshmallow often takes other forms, such as marshmallow fluff (also sometimes called marshmallow cream) and marshmallow “sauce,” most often paired with ice cream. These recipes often incorporate egg whites for stability, since they typically don’t contain gelatin. It should be noted that despite similarities in ingredients lists, these recipes are different from meringue: Meringue has more egg white than sugar, whereas marshmallow fluff and sauce recipes contain more sugar than egg white.

First thing's first: Play it safe.

While I’m a strong advocate that lots of candy-making is simple and can easily be made at home, let’s be real for a second: This is hot stuff, and you should take care to prevent injury. Remember to keep a safe distance and to use a candy thermometer, not a handheld one, to reduce the chance of burning yourself. Don’t touch the sugar directly, and handle the pot with oven mitts at all times. Use heat-safe utensils like wooden spoons or wooden-handled Silicone spatulas. When you pour the syrup into the bowl of your electric mixer, pour slowly to avoid splatters. When you turn your mixer on, raise the speed slowly to avoid splattering any hot syrup by turning it up too fast right away.

Ready your ingredients.

As with a lot of candies, the ingredient list is short and sweet (literally). While individual recipes may vary, most will contain gelatin, water (to bloom the gelatin and to add to the sugar mixture), sugar, corn syrup, and flavoring ingredients. The corn syrup is there to help prevent crystallization, and it’s a huge aid in the process. If you’re unsure about using corn syrup, read more on it here! You’ll also need plenty of confectioners' sugar to toss the finished marshmallows in (this helps them from feeling sticky to the touch and prevents them from sticking together once cut).

Nonstick spray is your new best friend.

When sugar syrup is whipped into a fluffy, aerated mixture, it’s super sticky. It just is. So give yourself a hand by keeping a bottle of nonstick spray (or a bowl of neutral oil and a clean kitchen towel) at the ready. You’ll want to use it not only on the pan you’ll ultimately pour the marshmallow mixture into, but also on all the tools you’ll need once it’s whipped and ready to go. For the recipe included in this article, that includes a medium offset spatula and a heat-safe Silicone spatula.

Prep your equipment ahead of time.

You'll need...
- A small pot for cooking the sugar
- A pastry brush in a bowl of water (see next bullet)
- A quarter sheet tray (9 by 13 inches) lined with parchment paper
- An offset spatula
- A Silicone spatula
- A pair of sharp kitchen scissors

Don’t forget to spray the lined pan and spatulas well with nonstick spray. Ready your electric mixer fitted with a whip attachment.

Pastry brush at the ready.

When cooking sugar syrups, you bring the mixture to a boil. Once it’s boiling, moisture begins to evaporate, which means that any sugar syrup that sloshed onto the sides of the pan will quickly turn into small crystals or granules of sugar. If any of these granules come in contact with the remaining syrup, it can cause the whole mixture to crystallize. This is why nearly all recipes remind you to brush down the sides of the pot with tepid water as needed to ensure that no sugar crystals ruin the mixture. But remember that every time you do this, you’re introducing more water into the syrup, which just means it will need to boil longer for it to evaporate away and reach the appropriate temperature. So brush away, but don’t go too crazy.

Bloom the gelatin.

The gelatin needs at least 5 minutes to bloom in cool water. For best results, start with the water in a small dish, and sprinkle the gelatin (in this recipe I use powdered rather than sheet gelatin) into an even layer on the surface of the water. Let it sit, undisturbed, for 5 minutes. It’s best not to stir, as the gelatin can form globs, and some of the gelatin on the interior of a glob may not come in contact with water, which can lead to an unpleasant graininess in your end product. You can do this process before you begin cooking your sugar, or during if you’re comfortable multitasking.

After the gelatin is bloomed, it's hydrated, but it still needs to be melted before it’s added to the sugar mixture. Do this just before you’re ready to add (as it will solidify again if it sits too long). For the recipe included in this article, it can be melted while the sugar syrup is cooling (see below). You can melt it in the microwave (15 to 20 seconds) or over a pot of simmering water.

More: Read more about using gelatin here.

Cooking the sugar.

Specific recipes may vary, but usually the sugar syrup will contain a small amount of water, granulated sugar, corn syrup, and flavoring. (If using an extract, add it during the whipping rather than the cooking process. But add other flavorings, like vanilla bean or citrus zest, during cooking to help infuse and distribute flavor throughout the syrup.)

Combine the ingredients in a small pot. Stir the ingredients to combine them and to start dissolving the granulated sugar. But the moment the mixture begins, to bubble, stop stirring! Agitating a boiling sugar syrup can encourage crystals to form, which can lead to disaster. Once you stop stirring, brush any excess sugar crystals away from the sides of the pot with your pastry brush and water (see above).

Once the mixture begins to boil, you’ll also need to fasten a candy thermometer to the side of the pot. Laser thermometers are also great for this, since they detect very accurate surface temperatures (and can be used from a safe distance). Cook the sugar until it reads 245° F. (At the beginning, the syrup’s temperature will rise very quickly, but the last 5 to 8 degrees can take a little bit. Never fear: This is normal!)

When the sugar reaches the correct temperature, carefully pour it into the bowl of an electric mixer fitted with the whip attachment. Cool the syrup to 220° F. While the syrup cools, melt the gelatin in the microwave (15 to 20 seconds) or over a pot of simmering water.

Whip the sugar.

When the sugar has cooled to 220° F, begin to whip it. Gradually work your mixer up to medium speed. Once the mixer is running, add the melted gelatin (and any extracts, if using).

Whip the sugar on medium speed until the bowl feels almost entirely cool to the touch and the sugar is opaque white and very fluffy, 4 to 5 minutes. It should hold stiff peaks. Try not to stop and restart the mixer multiple times, just keep whipping steadily for 4 to 5 minutes.

Shaping (part 1) & cooling.

From the moment you stop whipping, it’s important to work quickly. As the marshmallow mixture cools, the gelatin begins to set up. You want to be sure to get your marshmallow into the pan before it begins to set up too much, or it may spread unevenly and just be generally difficult to work with. Use your greased Silicone spatula to help remove the marshmallow from the mixer bowl, pouring it into the prepared pan. Use the greased offset spatula to spread the marshmallow into an even layer. The faster you do this, the smoother the surface of your marshmallow will be.

Once the marshmallows are in the pan, they need to be cooled completely before they can be cut into individual candies. Depending on the temperature of your room and the marshmallow mixture itself once it hits the pan, this can take as little as 45 minutes, but you can also leave it overnight. For longer storage, cover the surface of the marshmallow with plastic wrap that has been lightly greased with nonstick spray.

Shaping (part 2).

Once the marshmallows are cooled, they can be cut. Ready a large, shallow bowl or other vessel with plenty of confectioners’ sugar. My preferred tool for cutting marshmallow is a pair of sharp kitchen scissors, which I spray with nonstick spray to prevent sticking.

Cut the marshmallows into long strips about 1-inch wide. Take one strip in hand and, holding it over the confectioners’ sugar, cut the marshmallows into 1-inch squares, letting each fall into the confectioners’ sugar. Cut a few, toss completely in confectioners’ sugar, then transfer to a storage container. It’s best to add some extra confectioners’ sugar to the storage container to keep the 'mallows in a sugar bath at all times. Repeat with the remaining marshmallows and sugar.

Storing.

Marshmallows have a nice, long shelf life. Keep them in an airtight container with a little extra confectioners’ sugar. They should last for up to 3 weeks at room temperature.

Like many candies, the enemy of marshmallows is moisture, including humidity. Prolonged exposure to heat can also make them melt or otherwise deteriorate.