California Chicken Sandwich

I grilled the chicken just because it was easier and one less pan to wash. It turned out great. We didn't have avocado with it, but it was still very good. It's a really good sandwich for the summer. We had corn on the cob too.
Ingredients:

Citrus mayonnaise:
1/3 cup fat-free mayonnaise
2 tablespoons thawed orange juice concentrate
1 teaspoon lime juice
1/2 teaspoon ground cumin
1/8 teaspoon hot sauce

Sandwiches:
4 (4-ounce) skinned, boned chicken breast halves
1/4 teaspoon salt
1/8 teaspoon black pepper
Cooking spray
8 (1 1/2-ounce) slices diagonally cut sourdough bread, toasted
4 small romaine lettuce leaves
2 plum tomatoes, each cut lengthwise into 4 slices
1 peeled avocado, cut into 8 wedges

Preparation
To prepare citrus mayonnaise, combine first 5 ingredients in a small bowl.
To prepare the sandwiches, sprinkle chicken with salt and pepper. Place a large nonstick skillet coated with cooking spray over medium-high heat; add chicken. Cook 5 minutes on each side. Reduce heat to low. Cover; cook 5 minutes or until done. Remove from heat. Cut chicken diagonally across grain into thin slices.
Spread 1 tablespoon citrus mayonnaise on each of 4 bread slices. Top with 1 lettuce leaf, 1 chicken breast half, 2 tomato slices, 2 avocado wedges, and remaining bread slices.