Start by seasoning the boneless skinless chicken breasts with salt and pepper. Heat a skillet with olive oil over medium-high heat, ensuring it’s hot and shimmering. Cook the chicken for about 6-7 minutes on each side until it reaches a golden brown color and is fully cooked through (no pink in the center). Once cooked, remove from heat and let it rest for a few minutes to retain its juices.

While the chicken rests, slice the ripe avocado, cheese, red onion, and tomato. Aim for uniform slices, especially for the avocado, as it should be creamy and easy to layer. Remember, the cheese can be your personal preference—Swiss, Cheddar, or Provolone all work wonderfully.

Take two slices of your chosen bread and generously spread mayonnaise and Dijon mustard on both sides. Layer one slice with the rested chicken, followed by the creamy avocado, cheese, red onion, and tomato. Top it off with another slice of bread, making sure the mayo side is facing down.

Heat a skillet over medium heat and add a little butter or olive oil for extra flavor. Once hot, carefully place the assembled sandwiches in the skillet. Grill each side for 3-4 minutes, pressing down gently with a spatula until the bread is golden brown and the cheese is melting.

Once grilled to perfection, remove the sandwiches from the skillet and let them cool slightly. Now, slice them in half carefully to expose the gooey, delicious filling inside. Serve your Chicken Avocado Melt Sandwich warm for the best experience.