Preheat the oven to 180°C (350°F).
In a bowl, mix 250 grams of boneless chicken (cooked and shredded), 1/2 cup of grated mozzarella cheese, 1/4 cup of grated cheddar cheese, 1/4 cup of chopped coriander leaves, 1/4 cup of mayonnaise, 1/4 cup of chopped green bell pepper, and salt to taste.
In another bowl, mix 1/4 cup of softened unsalted butter, 4 minced garlic cloves, and 1/4 teaspoon of black pepper powder.
Slice a loaf of French bread or Italian bread into 1-inch thick slices, without cutting all the way through.
Spread the garlic butter mixture on both sides of each bread slice.
Stuff the chicken mixture between the slices, ensuring it is evenly distributed.
Wrap the stuffed bread in aluminum foil and bake for 15-20 minutes, or until the cheese has melted and the bread is crispy.
Remove from the oven, carefully unwrap the foil, and let it cool for a few minutes before serving.