1. Toast walnuts, if using. Preheat oven to 300 degrees F. Spread nuts evenly on a foil lined tray and toast until fragrant, about 4 minutes. Watch so they don't burn. Set aside.
2. Core and chop, but don't peel, Granny Smith apple. In a small bowl, toss it with lemon juice to minimize browning. Set aside.
3. Peel and coarsely chop carrots and cucumber. Cut onion and tomatoes into 1/2 inch chucks.
4. Put romaine on a cutting board and coarsely chop. You should have about 10 cups chopped. Transfer to a large salad bowl, along with prepared apple, carrots, cucumber, onion, and tomatoes. Add cheese and cooled nuts, if using. Pour on dressing and mix evenly. Serve immediately.
Source: Hannaford fresh Magazine, May - June 2007