Marinate the chicken with salt, pepper and olive oil.
Heat a griddle-pan with olive oil and cook the chicken, turning to make sure it gets perfectly seared on all sides. Add 3 tablespoons of water and cook with lid on till the chicken is cooked through.
Brush the toasted halves of the bread with pesto.
Place the chicken and cherry tomatoes on the bread and spread the grated mozzarella evenly.
Bake at 200*c for 5-6 minutes or until the cheese has melted and is brown.
Cherry tomatoes can be replaced with red peppers or zucchini for a change.