Slice the ham into 1/2-inch strips. Spray a nonstick skillet with cooking spray and preheat over a medium-high heat. Add the ham to the skillet and cook over stirring frequently, until the ham is warmed through and crisped, 3 to 5 minutes. Remove from the heat and set aside.
Remove and discard the yolk from 1 of the hard boiled eggs. Chop the remaining egg white and whole egg and set aside.
In a large bowl toss the romaine and watercress with 2/3 of the dressing. Put the dressed greens onto a large serving dish. Place the tomatoes on top forming a row down the middle. In strips on either side of the tomatoes place the avocado, chicken, cheese, diced egg, and the crisped ham on top of the greens. Drizzle with the remaining dressing and serve.