1. Lightly toast bread slices under broiler.
2. Spray large non-stick skillet with cooking spray.
3. Heat over medium high heat.
4. Add chicken breasts to skillet. Sauté 4 minutes, turn sauté 4 more minutes.
5. Remove chicken from stovetop. Top with chopped green onion and Swiss cheese.
6. Cover skillet and allow chicken to rest and cheese to melt.
7. Add mayonnaise, Dijon mustard, and dried oregano leaves, to small bowl.
8. Spread on toasted bread slices.
9. Arrange mixed spring greens over spread.
10. Top with chicken.
4 ounces French Bread, sliced diagonally in 4 pieces
4 (4 ounces) Boneless, Skinless Chicken Breast Halves, rinsed and patted dry
1/2 cup finely chopped Green Onion
2 ounces Swiss Cheese
2 tablespoons plus 2 teaspoons Light Mayonnaise
2 tablespoons Dijon Mustard