Preheat oven to 425°F (220°C) and line a baking sheet with parchment paper.
Slice the Italian bread in half lengthwise, then cut into smaller sections. Place cut-side up on the baking sheet.
In a bowl, mix softened butter, chopped scallions (reserve some for garnish), minced garlic, mayonnaise, garlic powder, black pepper, sugar, and salt until smooth.
Spread the garlic butter mixture evenly over the bread.
Combine mozzarella and Parmesan cheese, then sprinkle generously over the bread.
Bake the Cheesy Garlic Bread Recipe for about 15 minutes until the cheese is melted and golden.
Garnish with reserved scallions and serve warm.