Sweet Mix Steps
In a small saucepan combine the remaining 1/2 cup water, sugar, corn syrup and salt. Cover and heat over medium high for 3-4 minutes. Uncover, clip on your candy thermometer, and cook until the mixture reaches 240 (which should take about 7-8 minutes). Remove the pan from the heat immediately.
Turn your mixer on low, and slowly pour the sugar syrup into the bowl. When all the syrup is added, crank up the speed to high. Beat the mixture for about 6 minutes then turn the machine to low and add the maple syrup and rum. Increase the speed back up to high to fully incorporate the liquid and continue beating until the mixture is thick, glossy and has cooled slightly. It should take about a total of 12-15 minutes.
Generously coat a spatula with cooking spray and use it to turn the marshmallow mixture into the prepared pan. Spread the mixture evenly around the pan and all the way to the sides.
