Making homemade marshmallows is not as hard as you would think. In fact, I think they turn out better than the store-bought kind. They are softer and more tender.
Marshmallows contain mostly sugar, gelatin, and corn syrup. The gelatin is what gives the marshmallows their texture.
The first thing you do is soak your gelatin in water to thicken it up. This takes about 5 minutes. I use the bowl that goes to my stand mixer.
Meanwhile, in a two-quart pot combine the water, corn syrup, granulated sugar, and salt (if your recipe calls for it) and bring to a boil. Make sure to wash down the sides of your pot to prevent crystallization.
When the mixture reaches the softball stage (238-240º F) take it off the heat. Using a stand mixer, turn it on low -so as not to spatter- and pour your sugar mixture into the gelatin. Once you’ve poured all of the sugar mixtures in, turn it to high speed and allow it mix for about 15 minutes. It will be white and thick. Then add the vanilla – or whatever flavoring you decide on – and mix until it is all incorporated.
It will be quite sticky but you will need to spread it into buttered pan. Coat your spatula with butter to keep the marshmallow from sticking to it while you spread it in the pan. I recommend using a glass pan. (For some reason, I just have better luck with a glass pan.) If you decide to line your pan instead with some wax or parchment paper, be sure to sprinkle the bottom of it with powdered sugar to keep it from sticking. Once you spread the marshmallow sprinkle the top with powdered sugar. I like to use those wire strainers to dust the sugar on.
Let the marshmallow set up for a few hours and then using a knife or kitchen shears (dipped in hot water) cut the marshmallow and roll it in more powdered sugar to keep them from sticking.