French Onion Chicken Casserole

Ingredients

• 3 boneless, skinless chicken breasts
• 2 tsp garlic powder
• 1 tsp dried oregano
• Pinch of salt and fresh cracked pepper
• 300g shredded mozzarella cheese (or Gruyere)
• 2 tbsp unsalted butter
• 5 large onions, thinly sliced
• 3 cloves garlic, minced
• 300ml chicken broth
• Fresh chopped parsley, for garnish