Cut the mini baguette in half lengthwise. Spread mayo generously on one or both cut sides.

Layer turkey, salami, and mozzarella slices on the bottom half of the baguette.

Place the open sandwich on a baking sheet and broil for 2 minutes until the cheese starts to melt and the edges are golden. Watch closely so it doesn't burn.

While the sandwich is in the oven, add the lettuce, white onion, and olives to a cutting board. Drizzle over the mayo, vinegar, salt, pepper, and chili flakes.

Using a large knife, chop and mix everything together until well combined and finely chopped.

Remove the sandwich from the oven. Pile the lettuce mixture generously on top. Close the sandwich and wrap tightly in parchment paper.

Cut in half and enjoy!