Whisk oil, vinegar, honey, mustard, salt and pepper in small bowl until well blended. Add the 1/4 cup blue cheese; mix lightly. Set aside.
Place lettuce in large bowl; add half of the walnuts. Pour dressing over lettuce; toss until coated.
Place equal amounts of salad onto 4 plates. Top each evenly with apple, the 1/2 cup blue cheese and the remaining walnuts. Serve immediately.