Preheat oven to 350 degrees. Combine sugar and salt in a large bowl.
Bring a small saucepan of water to a boil. Add walnuts, and blanch 2 minutes. Drain, and immediately toss with sugar-salt mixture.
Transfer walnuts to a rimmed baking sheet, and bake, stirring occasionally, until golden brown, about 10 minutes. Let cool.
Sugared walnuts can be stored in an airtight container at room temperature for up to 3 days.