Place bacon in a large skillet and cook over medium-high heat, turning occasionally, until evenly browned, about 7 minutes. Drain bacon slices on paper towels; reserve the grease.
Place the cooked bacon in a food processor; process until finely chopped.
Preheat oven to 350 degrees F (175 degrees C).
Beat sour cream and cream cheese in a bowl until smooth. Add the bacon pieces, green bell pepper, and green onion; blend until evenly combined.
Cut about a 1/2-inch slice from the top of the round bread loaf. Scoop out the center, reserving the pieces of bread. Baste the inner surface of the bread bowl with the reserved bacon grease. Place the bread bowl, the reserved pieces of bread, and sourdough bread pieces in a baking pan.
Bake in the preheated oven until lightly toasted, about 20 minutes. Remove and fill the bread bowl with the cream cheese mixture. Return to the oven and continue baking until the filling is bubbling, about 20 minutes more.