Cook your bacon in a skillet. Use medium heat. Keep stirring until it is crisp. This might take fifteen to twenty minutes. Remove the bacon from the skillet and place it on paper towels to get rid of the excess fat. Allow the bacon to cool.
Place your eggs in a medium sized source pan. Cover the eggs with water and bring to simmer. Cover the pan and remove from heat. Allow the eggs to stand for about ten minutes. Drain the excess water and run some cold water to cool the eggs. For the best results, peel the eggs under cold running water. Separate the yolk and the white. Chop the eggs and season with some salt.
In a large bowl, toss your lettuce and watercress.
Start composing your salad. Arrange the bacon, avocado, chicken and tomato over the lettuce and watercress decoratively. Garnish your salad using the chives and chopped eggs whites and yolk.
The vinaigrette is the last thing you are going to make. Whisk the vinegar, salt, pepper, and mustard in a small bowl. While whisking, add the oil. Continue to wish this dressing until it gets emulsified. Add the Roquefort and keep stirring. Add the sugar to taste. Serve separately.