Don't you just love the look of homemade marshmallows? Cut into squares and dusted with powdered sugar, they look and taste so much better than their cylindrical grocery store cousins. Making them is probably easier than you think! I've never been a super hard core baker of things from scratch so when I say they're not too difficult to make, I mean it!
This DIY is based on a recipe from Joy of Baking
1 cup cold water, divided
3 - 1/4 ounce envelope unflavored gelatin
2 cups granulated white sugar
1 cup light corn syrup
1/4 teaspoon salt
2 teaspoons pure vanilla extract
4-5 cup confectioners' (powdered) sugar, sifted
Lightly butter, or spray with a non stick vegetable spray, the bottom of a 13x9x2-inch (33x23x5-cm) baking pan. Line the bottom of the pan with parchment paper. The vegetable spray helps the parchment paper stick to the pan more securely. Then sift about 3 tablespoons of confectioners' (powdered) sugar onto the bottom of the pan (this will help release the set marshmallow from the paper later on).
Place 1/2 cup cold water into the bowl of your electric mixer that is fitted with a whisk attachment. Sprinkle the gelatin over the water and let stand until gelatin softens, about 15 minutes.
Meanwhile, in a heavy two quart saucepan, place the sugar, corn syrup, salt, and remaining 1/2 cup cold water. Stir over medium heat until sugar dissolves and the mixture comes to a boil. Cover the saucepan with a lid and let boil for about three minutes to allow any sugar crystals to dissolve from the sides of the saucepan. Then the recipe says to remove the lid and attach a candy thermometer to the side of the pan. Increase heat to high and boil, without stirring, until the syrup reaches 240 degrees F, about 10 minutes. I don't have a candy thermometer so I just set a timer for 10 minutes and then removed the syrup from the heat and it turned out fine.
With mixer running at low speed, slowly pour the hot syrup into the gelatin mixture in a thin stream down the side of the bowl.
Gradually increase the speed to high and beat until mixture has tripled in volume and is very thick and stiff, about 10 minutes (looks like thick marshmallow cream). Add vanilla extract and beat to combine, about 30 seconds longer.
Scrape marshmallow mixture into the prepared pan and spread with a rubber spatula. To say that this mixture is sticky is an understatement so just smooth it out as best as you can. Dust the top of the marshmallow with another 3 tablespoons of confectioners' sugar and let stand, uncovered, at room temperature until set, about 12 hours.
Remove the marshmallow from the pan by first running a small sharp knife around the edge of the marshmallow to loosen it from the pan. Invert the pan onto a large cutting board that has been dusted with confectioners' sugar. You will have to use your fingers to help loosen the marshmallow from the pan. Peel off the parchment paper (the marshmallow will be sticky) and dust the top of the marshmallow with confectioners' sugar.
Cut the marshmallow into squares using clean kitchen scissors, a pizza roller or a sharp knife. Dip the cut sides of the marshmallows in additional confectioners' sugar. Shake off excess sugar and store the marshmallows in an airtight container, at room temperature, for up to two weeks.