Preheat the oven to 400 °F.
Use a serrated bread knife to cut off the top 1 inch or so of the bread loaf. Scoop out the soft bread inside. Cut the top and inside into bite-sized pieces. Set these all aside to serve later.
Combine the cream cheese, sour cream, shredded mozzarella cheese, and garlic powder in a heat-safe bowl. Fold in bacon and green onion, reserving some for garnish.
Microwave this on high for 3 minutes, or heat slowly while stirring frequently in a small saucepan over medium heat until warm.
Place the bread bowl on a baking sheet and pour the dip into it. Top with the cheddar cheese and bacon and onion garnish. Bake for 10 minutes until the cheese is melted. Serve warm.
