Preheat the oven to 350 degrees F. Spray a heavy baking sheet with vegetable oil cooking spray.
In a medium bowl, whisk the egg white and salt just until foamy. Add the maple syrup, rosemary and cayenne pepper. Stir in the nuts and sunflower seeds and toss until coated.
Spread the nut mixture on the prepared baking sheet in a single layer. Bake until the nuts are crisp and brown, 20 to 25 minutes, stirring halfway through. Let cool before serving or storing.