Have a clean plate ready near the stove. Place the walnuts in a small, heavy nonstick skillet. Sprinkle on the sugar and spices. Cook over medium heat, stirring constantly with a wooden spoon, until the sugar melts, 3 to 5 minutes. Almost all of the sugar will cling to the walnuts. Immediately dump out the walnuts onto the plate to cool. If you leave them in the hot skillet even a moment too long, they will burn. These can be made a day ahead and stored at room temperature until needed.