Ingredients:

  • 1/2 cup Confectioners' Sugar
  • 1/2 cup Cornstarch
  • 3 Tbsp Unflavored Gelatin Powder (about 4 packets)
  • 1/2 cup Cold Water (for gelatin)
  • 1 1/2 cups Granulated Sugar
  • 1 cup Light Corn Syrup
  • 1/2 cup Water (for syrup)
  • 1/4 tsp Salt
  • 2 tsp Pure Vanilla Extract

Instructions:

  1. Grease a 9x13 inch pan lightly, then line it with parchment paper, allowing an overhang on the two long sides for easy lifting. Sift the dusting mixture (confectioners’ sugar and cornstarch) generously over the parchment-lined pan, ensuring the bottom and sides are coated thoroughly. Set aside.
  2. Pour the cold water into the bowl of the stand mixer. Sprinkle the gelatin powder evenly over the water. Allow the mixture to 'bloom' (thicken and gel) for 5 to 10 minutes while preparing the syrup.
  3. Combine the granulated sugar, corn syrup, 1/2 cup water, and salt in a heavy saucepan. Stir gently over medium-high heat until the sugar dissolves. Stop stirring once the mixture comes to a full rolling boil.
  4. Clip the candy thermometer to the side of the pan. Continue boiling without stirring until the syrup reaches precisely 240°F (116°C) (Soft-Ball Stage). This usually takes 8–10 minutes.
  5. Once the syrup hits 240°F (116°C), immediately turn the stand mixer on low speed to loosen the bloomed gelatin.
  6. With the mixer running on low, slowly and steadily pour the entire hot sugar syrup down the side of the bowl (avoiding the whisk). Gradually increase the mixer speed to medium-high.
  7. Continue whipping for 12 to 15 minutes. The mixture will increase significantly in volume, become opaque white, and transform into thick, marshmallow fluff. It is finished when it holds stiff, satiny peaks and the outside of the mixing bowl is cool to the touch.
  8. Turn the mixer to low and briefly mix in the vanilla extract until just incorporated.
  9. Immediately scrape the marshmallow mixture into the prepared pan using a lightly oiled spatula. Gently spread the mixture into an even layer, working quickly as it sets fast.
  10. Let the marshmallows cure, uncovered, at room temperature for a minimum of 2 hours (preferably 4 hours or overnight) until firm and dry to the touch. Lift the slab out of the pan using the parchment paper overhang. Dust a sharp knife or pizza cutter with the dusting mixture, and cut the slab into desired squares. Toss the cut edges in the remaining dusting mixture until fully coated.