To prepare dressing, combine first 5 ingredients, stirring well with a whisk.
To prepare salad, sprinkle chicken with salt and 1/4 teaspoon pepper. Heat a nonstick grill pan coated with cooking spray over medium-high heat. Add chicken; cook 5 minutes on each side or until done. Cut chicken into thin slices, and keep warm.
Place greens in a large bowl. Drizzle 1/4 cup dressing over greens; toss gently to coat. Combine rice and remaining dressing, tossing to coat.
Divide the greens evenly among 4 plates, and spoon 1/2 cup rice mixture over each serving. Top each serving with 1 chicken breast half; sprinkle each serving with 1/4 cup cheese, 2 tablespoons currants, and 1 1/2 teaspoons nuts.