Preheat oven to 350F.
Place the chopped walnuts on a baking sheet and bake for 5-7 minutes, or until toasted.
Add the walnuts to a medium bowl along with the remaining salad ingredients and toss until well combined.
In another bowl, combine the oil, balsamic vinegar, salt, pepper and mustard, Whisk until well combined.
Toss the salad with the dressing until well coated.