This is a wonderful dip that I've made a few times around here, including on New Year's Eve. I like to serve it with slices of French bread.
adapted from a Betty Crocker magazine
1/2 head romaine lettuce, chopped
1 cup sour cream (fat-free and low-fat are okay)
1/2 package ranch dip mix (or 1 tablespoon buttermilk powder, black pepper to taste, a pinch of garlic powder, and 1/2 teaspoon parsley)
1/4 to 1/2 pound bacon, cooked and crumbled
2 tomatoes, chopped, salted, and left to drain for 15 minutes
2 green onions, chopped
Spread the lettuce on your serving dish. Mix together the sour cream, ranch dip mix, bacon, and about 3/4 of the green onions. Layer half the sour cream mixture on top of the lettuce, then half the tomatoes, then the remaining sour cream mixture and tomatoes. Garnish with reserved green onions.