Preheat the oven to 400F.
Mix peeled garlic cloves with olive oil and salt; place in a small oven-safe pot with lid or cover with foil. Roast for about 20 minutes until soft and golden.
Mash roasted garlic with a fork and set aside.
Reduce oven temperature to 350F.
In a bowl, whisk together mashed roasted garlic, melted butter, egg, milk, salt, paprika, and chopped parsley until combined.
Cut sheet of bread rolls horizontally into two halves and place on a baking sheet. Bake for 8-10 minutes until lightly golden and crispy.
Pour garlic butter custard into a larger pan. Carefully dip both bread halves into the custard, coating all sides well.
Return bread to baking sheet and bake at 350F for 15-18 minutes until golden.
Sprinkle shredded mozzarella evenly over the bread.
Switch oven to broil and broil for about 5 minutes until cheese is melted and golden.
Garnish with fresh parsley and chili flakes.
Slice and serve warm for a delicious cheesy garlic bread experience.