Source: Good Things Catered
4 envelopes unflavored gelatin
3 c. granulated sugar
1 1/4 c. light corn syrup
1/2 tsp salt
1 Tbsp vanilla extract
powdered sugar for slicing
In large saucepan over medium high heat, combine 3/4 c. water, sugar and corn syrup.
Meanwhile, in bowl of stand mixer place 3/4 c. water and sprinkle gelatin on top, let plump.
Bringing sugar mixture to boil, place candy thermometer in middle of mixture, making sure not to touch the side or bottom of the pan and let keep a rolling boil until mixture passes 235 degrees, about 3-5 minutes.
With mixer on low, carefully pour sugar mixture into mixer bowl, add salt and slowly raise beater to high speed.
Beat sugar mixture on high for five minutes and then add vanilla. (If you’d like to add other flavors here like peppermint, color, or cocoa powder for chocolate, add now).
Continue beating mixture for an additional 5 minutes.
Meanwhile, oil a 9×13 pan for large marshmallows or two 10×10 pans for small marshmallows.
When done beating, pour sugar mixture into pan(s), smooth top and tap to release extra air.
Leave on counter overnight to form.
Generously sprinkle working surface with powdered sugar, turn out marshmallow mixture, generously sprinkle with powdered sugar, and cut as desired, lightly coating marshmallow shapes with powdered sugar to avoid sticking.
9×13 pan makes about 96 large marshmallows that can be stored in a container for about a week.