In a 2 to 3 qt saucepan, whisk together the sugar, corn syrup, and water. Heat the mixture over medium heat until the sugar is dissolved, stirring often.
Increase the heat to high and stop stirring. Heat until a candy thermometer reads 250º. Meanwhile, using a stand mixer, beat egg whites until stiff peaks form.
Slowly, add the heated sugar mix to the egg whites while beating the mixture at medium speed. It should take around 2 minutes to add the sugar mixture. Next add the vanilla.
Mix the divinity on medium speed for 15 to 20 minutes, stopping to rest the mixer for 2 to 3 minutes every five minutes. When the divinity is ready, the mixture will no longer be shiny and glossy. It should instead appear almost matte and it should hold its shape if spooned out.
Working fairly quickly, use two greased spoons or a 1.5 Tbsp greased cookie scoop to place the divinity onto waxed paper to set. Wait at least a few hours before storing.
Store divinity in an airtight container at room temperature for up to two weeks. Enjoy!
Notes
Walnuts or pecans can be added. Fold in the nuts after the divinity has turned matte in appearance.