Prepare the bread: Slice the mini sandwich bread or dinner rolls in half horizontally. If using dinner rolls, hollow out some of the bread to make room for fillings.

Make the spread: In a small bowl, mix mayonnaise and Dijon mustard. Spread a thin layer on the inside of each bread half.

Layer the meats and cheeses: Place a slice of ham, turkey, cheddar, and Swiss cheese on the bottom half of each bread piece.

Add the vegetables: Top the meats and cheeses with shredded lettuce, tomato slices, and cucumber slices. Season with a pinch of salt and pepper.

Assemble the sandwiches: Place the top half of the bread over the fillings. Press gently to secure.

Serve or store: Serve immediately or wrap in plastic wrap and refrigerate until ready to serve. Cut into smaller pieces if desired.