Preheat oven to 350°F (175°C). Line a baking sheet with foil.
Slice the French bread in half lengthwise and scoop out the center of each half to make room for filling.
In a large skillet, cook ground beef over medium heat until no longer pink. Drain excess fat.
Add chopped onion, bell pepper, garlic, salt, and pepper. Cook until vegetables are softened, about 5 minutes.
Stir in cream cheese and sour cream until melted and combined.
Remove from heat and mix in shredded cheddar cheese.
Spoon the beef mixture into the hollowed-out bread halves and place on the prepared baking sheet.
Bake for 15-20 minutes, or until cheese is melted and bread is toasted.
Sprinkle with chopped parsley before serving, if desired. Slice and serve warm.