1 large round bread loaf or boule (about 8 inches in diameter)
3 to 4 tablespoons Dijon mustard
12 ounces thinly sliced smoked cooked turkey
4 ounces sliced cheddar cheese
2 ounces butter lettuce leaves (about 1 small head)
Cut the bread in half horizontally. Hollow out and remove most of the soft interior of the bread from each half and save for another use, like DIY breadcrumbs.
Spread the cut sides of the bread with mustard. Layer the turkey and cheddar inside the bread bottom. Top with butter lettuce. Place the top on the sandwich, tightly wrap the sandwich in 2 layers of plastic wrap, then refrigerate for at least 1 hour or up to 1 day.