1
Stir together the sugar, agave, and ½ cup water in a saucepan. Bring the mixture to a boil over medium-high heat while stirring occasionally to help heat the sugar syrup evenly. Cover the saucepan, lower the heat to medium and cook for 3 minutes.
2
Remove the lid and place a sugar thermometer in the syrup. Continue heating the syrup until it reaches 118°C. While the sugar syrup cooks, prepare the gelatin.
3
Place the remaining ½ cup water in the bowl of a stand mixer fitted with a whisk attachment. Sprinkle the gelatin over the water and stir to combine. Let the gelatin bloom for at least 10 minutes, or until the syrup reaches temperature.
4
Once the sugar reaches 118°C, remove from the heat allow it to cool for about 2 minutes. Add a pinch of salt to the gelatin.
5
Before adding the sugar to the gelatin mix, start the mixer on medium speed. Slowly pour the sugar syrup into the gelatin along the sides of the bowl to prevent the gelatin from overheating. Gradually increase the speed while adding the sugar until the mixture is completely combined. Increase the speed to the highest speed and let the marshmallow whisk on high for about 4-5 minutes, until it’s white, light and fluffy and at least tripled in size.
6
While the marshmallow is whisking, line a 9 x 13 inch with parchment paper and brush on some unflavored oil, or rub the pan directly with shortening or butter. Brush all utensils with the oil as well (spatulas and spoons).
7
When the marshmallow is whipped and has tripled in size, add the vanilla extract and orange blossom water and continue to whisk on high for 1 minute to mix thoroughly.
8
Remove the marshmallow mix from the mixer and scrape it into the prepared pan. Using an oiled offset spatula, spread the marshmallow evenly in the pan. Sprinkle the pistachios over the top and gently press them into the marshmallow surface so they stick.
9
Allow the marshmallow to set for at least 6 hours. When the marshmallow has set, release it from the pan and place it on a surface dusted with confectioner’s sugar. Using an oil-brushed knife, cut the marshmallow into squares.
10
Dust the sides and bottom of the marshmallow squares with confectioner’s sugar and place them in a dry, air-tight container until ready to serve.