Pour the 3 packets of gelatin and 1/2 cup of the cold water into the bowl of your stand mixer and allow it to absorb into the water. This is called "blooming" the gelatin. Affix the whisk attachment to your mixer.
In a saucepan, add the remaining 1/2 cup of water, sugar, salt, and corn syrup. Place over medium heat and cook, covered, for 3 to 4 minutes. Uncover and allow to cook for another 8-9 minutes until the syrup reaches 240 degrees F. Remove from the heat.
Turn your stand mixer on low to mix the bloomed gelatin around.
Slowly stream the hot syrup into the stand mixer, being careful to not pour it directly onto the gelatin but instead down the side of the mixing bowl.
Once the syrup is completely added, slowly and carefully turn the mixer up to high and allow it to mix for 15-20 minutes. The longer you let it mix, the firmer the finished marshmallows will be.
Sift your Matcha into a bowl and then mix in some hot water with a Matcha whisk or the back of a spoon until it is smooth with no lumps. Stream the dissolved Matcha into the marshmallow mix during the final minute of mixing. (i.e., if you plan on mixing the marshmallows for 17 minutes total, add the Matcha at minute 16.)
Mix the corn starch and powdered sugar together. Lightly spray a baking pan with cooking spray and then add in the cornstarch-sugar mixture. Tilt the pan until it is lightly coated in sugar-cornstarch. Remove any excess and save it for later.
Pour the finished marshmallow batter into the pan and allow it to sit for at least four hours.
Cut with any shape cookie cutters you like. (You can also use a knife to cut 1 inch square marshmallows.)
Lightly toss each cut marshmallow in the remaining cornstarch-sugar mixture, tapping off any excess. (Note: If you would like your finished marshmallows to have a stronger tea flavor, you can sift one to two teaspoons of Matcha into the cornstarch-sugar mixture before tossing the marshmallows in it.)
Tip: Even if you don't have cookie cutters to cut out shapes, you can cut the marshmallows into squares with a knife.
Note: A kitchen stand mixer is necessary for this recipe.
Acknowledgement: This recipe is derived from Alton Brown's "Homemade Marshmallows" recipe available on Food Network.
Click below to purchase the culinary Matcha used in this recipe: