simply delicious simple sandwich — Les Petites Gourmettes

Ingredients

• 4 large white and/or red onions, peeled and thinly sliced
• 2 tablespoons olive oil
• 4 garlic cloves, peeled and minced
• 1 1/2 teaspoons sugar
• 1/4 cup balsamic vinegar, preferably white balsamic
• 1/4 cup chopped golden raisins
• Salt and freshly ground black pepper
• 1/2 cup prepared mayonnaise
• 2 to 3 tablespoons Sriracha sauce
• Shredded breast meat from Ginger & Star Anise Poached Chicken
• 1 bunch watercress; washed, stemmed, and spun dry