Preheat your oven to 350°F and line a baking sheet with parchment paper. Using a serrated knife, carefully make slits in the bread about 2 inches apart, making sure not to cut all the way through (think Hasselback-style!).
In a small bowl, whisk together the melted butter, garlic powder, Italian seasoning, salt, and red pepper flakes. Brush this flavorful mixture over and inside the bread, ensuring it gets into all the nooks and crannies. Place the prepared bread on the baking sheet.
Slice the brie into small pieces and stuff the bread with shredded mozzarella and brie slices. Sprinkle the top with Parmesan cheese to add an extra layer of flavor.
Bake the bread in the preheated oven until it’s toasted on top and the cheese is gloriously melted, which should take about 15 minutes.
Once out of the oven, garnish your cheesy masterpiece with parsley and serve it warm. Get ready for cheesy garlic bread bliss!