Slice the round loaf of bread in half horizontally.
Scoop out some of the bread from the inside to create space for fillings.
Spread a generous layer of olive salad on the bottom half of the bread.
Layer the ham slices evenly over the olive salad.
Add salami slices, ensuring even coverage.
Place slices of mortadella on top of the salami.
Add slices of provolone cheese over the mortadella.
Top with mozzarella cheese slices.
Add fresh lettuce if desired.
Close the sandwich with the top half of the bread, pressing down gently.