Preheat oven to 375 degrees F. Using a pointed serrated knife or other sharp knife, cut the top of the bread off, using the Brie wheel as a guide for the size of the circle.
Cut the top of the bread into rough cubes and place on a baking sheet. Pull more bread out of the center where the cheese wheel will be placed. Tear the bread into chunks and place on the baking sheet with the other cubes. Drizzle the cubed bread with 2 tablespoons olive oil and season with italian seasoning, salt and pepper. Toss to combine, then push to one side of the baking sheet, making room for the boule.
Carefully cut the skin off the top of the cheese, then nestle the cheese in the center of the boule. Place the boule on the baking sheet with the cubed bread and bake until cubes are toasted and cheese is melted, about 15 minutes.
In a small saucepan over medium heat, combine balsamic vinegar and sugar. Bring to a simmer and reduce by half to make a syrup. Remove from heat and let cool slightly.
In a medium bowl, combine the tomatoes, 2 tablespoons olive oil, garlic, basil, salt and pepper.
To finish, top the melted cheese with shredded lettuce. Use a slotted spoon and top the lettuce with the tomato mixture, then top with the chopped bacon. Drizzle over the balsamic reduction and sprinkle over scallions for garnish.