Preparation

• Soften the gelatin in 3/4 cup of the water in a small saucepan. Heat the gelatin slowly to fully dissolve it, but don’t let it fully boil. Stir in the vanilla.
• 在平底锅中，将糖，玉米糖浆和剩余的3/4杯水混合在一起。放在中火上并搅拌直至糖溶解。增加热量并将混合物煮沸。在锅中设置一个糖果温度计，不搅拌，让混合物煮沸，直到达到250°至260°F（硬球阶段）。当糖混合物沸腾时，将蛋清打成一块带有搅拌附件（或带有手持式搅拌机的高速）的立式搅拌机的蛋清，直到它们形成中型峰值。
  
• When the sugar syrup reaches temperature, whisk in the dissolved gelatin. Turn the mixer back on to the highest speed. Slowly pour the hot sugar syrup into the whisked egg whites, avoiding the whisk. The whites will get liquidy at first but will eventually thicken. Continue beating until the marshmallow mixture thickens enough to hold its shape, about 5 minutes; it will still be slightly warm.
  

• Lightly oil two 8-inch-square pans and then dust them with some of the cornstarch and confectioners’ sugar mixture. Divide the marshmallow mixture between the two pans, smooth it as flat as you can with a spatula, and let it sit uncovered until it’s springy and firm, 4 to 6 hours.
  

• Using your fingers or a sharp knife, loosen the marshmallows from the sides of the pans. Dust a long sheet of waxed paper with more of the cornstarch mixture. Flip the marshmallows onto the paper. Dust the surface with more of the cornstarch mixture and let the marshmallows sit for about 2 hours.

• 用锋利的刀或剪刀将棉花糖切成大约1-1/2英寸宽的条，然后进入正方形。棉花糖可能不会粘在刀或剪刀上，但是如果这样做，请尝试为刀片上油。