Preheat the oven to 250 degrees F. Beat the egg white with 1 tablespoon water in a large bowl until foamy. Add the nuts, sugar, cumin, cayenne, cinnamon and 1/2 teaspoon salt and mix well. Spread the mixture on a parchment-lined baking sheet. Bake until the nuts are mostly dry but still slightly sticky, about 40 minutes.
Remove the nuts from the oven and stir. Reduce the temperature to 200 degrees F. Return the nuts to the oven and bake until crisp, about 30 more minutes. Stir to loosen the nuts from the baking sheet; cool completely on the sheet.