10 cups chopped romaine lettuce
2 cups seedless red grapes, halved
1/2 cup chopped celery
1/2 cup chopped pecans, plus additional for optional topping
1/3 cup dried cranberries
2 red-skinned apples, such as Gala, skin on, chopped
1 Granny Smith apple, skin on, chopped
3/4 cup reduced-fat mayonnaise
3/4 cup skim milk
3 Tbsp. fresh lemon juice
3 Tbsp. grated Parmesan cheese
3/4 tsp. garlic powder
pinch salt
1/4 tsp. freshly ground black pepper