Preheat the oven to 350°F (175°C).
Prepare the filling: In a mixing bowl, combine crawfish tails, softened cream cheese, shredded cheddar cheese, chopped green onions, minced garlic, Cajun seasoning, and hot sauce (if using). Mix well until the ingredients are evenly incorporated.
Prepare the bread: Slice the French bread loaf in half lengthwise. Gently hollow out the center of each half, leaving about 1/2 inch of bread on the sides.
Fill the bread: Spoon the crawfish mixture into the hollowed-out halves, spreading it evenly.
Bake: Place the filled bread halves on a baking sheet and bake for 20-25 minutes, or until the top is golden brown and the filling is bubbly.
Serve: Let the crawfish bread cool for a few minutes before slicing. Serve warm and enjoy!