Lightly grease the bowl of your slow cooker, then add the almonds.
In a mixing bowl, combine both sugars, the cinnamon, and salt. Stir to evenly mix.
In a separate mixing bowl, whisk together vanilla and egg whites.
Pour egg white mixture over the almonds and toss to coat.
Add the sugar mixture to the almonds, and again, toss to coat.
Cover and let cook on low for 3 to 3 1/2 hours, stirring every 20-30 minutes.
Stir in the water then cover and cook another 20-30 minutes.
Meanwhile, prepare 1 or 2 baking sheets by lining with parchment paper. Once the almonds have finished, transfer them to the baking sheet, spreading them out to an even layer, leaving as few clumps as possible. Let them cool to harden, and enjoy!