Step 1

Prepare Vinaigrette: Combine first 6 ingredients in a medium bowl. Whisk until blended. Add olive oil gradually, whisking constantly after each addition. If made in advance, cover and refrigerate. Shake well before using.

Step 2

Prepare Cobb Salad: Wash, dry, and place watercress, romaine, and radicchio in a large bowl.

Step 3

Toss with enough dressing to lightly coat the leaves and transfer to a platter or individual plates. Arrange avocado, diced cooked chicken, crumbled bacon, hard boiled eggs, tomatoes, green onions, and blue cheese in rows on top of the greens.

Step 4

Lightly drizzle vinaigrette over the salad(s) and serve.