Special Equipment: A candy thermometer and a freestanding mixer.
Read through the entire recipe before starting to cook. Assemble everything and then begin. Once you are rolling, things move quickly. Marshmallows keep, covered, at room temperature three days. Do this once, and you will get the recipe's rhythm down easily.
2. In a little saucepan, combine the gelatin with half the water and set aside. Put the rest of the water into a little saucepan fitted with a candy thermometer. Add half the corn syrup and the sugar.
3. Put the remaining corn syrup, and the vanilla into the large bowl of an electric mixer fitted with a whip attachment.
4. Heat saucepan over medium high until the syrup bubbles and reaches 240 on candy thermometer. Do not stir. Have the mixer running at high spread. Stand back as you pour the hot syrup over the beating corn syrup. Beat 3 to 5 minutes.
5. Meanwhile, melt the gelatin over medium heat. Pour it into the beating mixture and beat another 6 minutes, or until white and very fluffy. You now have marshmallow in all its very sticky glory. Pour and scrape all the fluff into the foil, spread to even out and cool thoroughly. Cut with a wet knife. Seal and store in an airtight container up to 3 days.
Adam Rapoport, editor in chief of Bon Appetit magazine and the website www.bonappetit.com, knows his way around a grill. He has edited an entire book on the subject: The Grilling Book: The Definitive Guide from Bon Appetit.