3 Tbsp. unflavoured gelatin powder (3 packets)
½ cup and 2 tablespoons of cold water
1 Tbsp. vanilla extract
1 Tsp. maple extract
¾ cup water
1 ¼ cup dark corn syrup
1 ½ cups granulated sugar
2 cups powdered sugar, divided
1 cup corn starch, divided
Prepare a 9×13 in baking pan with cooking spray. (Ensure the entire dish is coated, as the marshmallow mixture is very sticky. Combine ½ cup of powdered sugar with ¼ cup cornstarch. Sift mixture into the baking dish and shake so the dish is coated. Set aside.
In a large bowl combine gelatin, vanilla extract, and maple extract with ½ cup and 2 tablespoons of cold water. Gently whisk mixture until well combined and no lumps remain. Continue to whisk until the gelatin reaches a consistency similar to baby food (about one minute). Set aside.
In a medium saucepan combine ¾ cup water, corn syrup, granulated sugar, and salt. Whisk to combine and bring to a boil over medium high heat. Cover pot, reduce heat and simmer for about 2 and a half minutes. Remove from heat.
Pour mixture over gelatin and beat on medium with an electric mixer until combined, about one minute. Increase speed to maximum and beat for 15-20 minutes until the mixture is glossy and makes meringue like peaks.
Pour marshmallow mixture into prepared 9×13 inch dish and spread evenly. Wet spatula and smooth the top until it’s even.
Leave the marshmallow mixture uncovered on a counter for 24 hours to set.
Once the marshmallows have set, prepare your workspace. Combine remaining powdered sugar and cornstarch in a medium sized bowl. Dust some of the mixture onto a cutting board.
Wet a sharp knife and drag it along the edges of the 9×13 inch dish to loosen the marshmallow mixture. Sprinkle some of the powdered sugar onto the top of the marshmallows and flip the dish onto prepared cutting board.
Cut the marshmallows into squares, occasionally wetting the knife to make more precise cuts. Toss marshmallow squares in the cornstarch sugar mixture until well coated.
Store marshmallows in a sealed container, layered between wax paper.