Juicy Chicken and Avocado Sandwich - Iam Cooker

Ingredients

• 2 chicken breasts, no skin or bones
• Pinch of salt and pepper
• 1 tablespoon olive oil
• 1 ripe avocado, cut into slices
• 4 slices of your favorite cheese (try provolone, cheddar or Swiss)
• 4 slices sourdough or ciabatta bread
• 2 tablespoons mayo
• 1 tablespoon Dijon mustard
• Some butter or olive oil for the pan
• 1 small red onion, sliced thin
• 1 fresh tomato, cut into rounds