Give your slow cooker a quick spray with the cooking spray, then add the egg white to your slow cooker, and beat with a fork until frothy. Add everything but the nuts, and stir until you have a thick, homogeneous syrup. Pour in the nuts, gently stir to coat, and cook on low for three hours, or high for one. Stirring them every hour or so will ensure they cook evenly, but it's not really necessary