Set up a clean cutting board with plenty of room and gather every ingredient. For this recipe, mise en place matters: place the deli meats, provolone, lettuce, cherry tomatoes, red onion, pepperoncini, Italian vinaigrette, mayonnaise, oregano, salt, and pepper near your board. If you have room, pop your mixing bowl and bread in the fridge for 10 minutes so the sandwich stays cold even during assembly. This step is not just about organization; keeping ingredients chilled reduces the risk of the mayonnaise and dressing turning greasy, and makes the chopping process a pleasure rather than a scramble. A large chef’s knife (8-inch or 10-inch) and a sturdy cutting board will give you the control needed for a clean, uniform chop, which is the heart of a great chopped Italian sandwich.

Prepare your bread. If using one long Italian loaf, slice it into four equal sections, then split each section horizontally leaving one side intact like a hinge. If using sub rolls, slice them open. Use your fingers to pull out some of the soft crumb from the top half, leaving a sturdy shell about 1/2 inch thick. This creates a little cavity to hold the chunky filling without it spilling out and also helps prevent the bread from turning soggy. You can reserve the pulled-out bread to make breadcrumbs later. At this stage, if you want a lightly crisp exterior, toast the cut sides under a broiler or in a dry skillet for 60 to 90 seconds. Let the bread cool completely before filling, because warm bread will create condensation and make the filling weep.

Stack and chop the meats. Lay the genoa salami, capicola, and mortadella slices in separate stacks of four or five. Roll each stack into a tight cylinder and slice crosswise into 1/4-inch ribbons, then gather the ribbons and chop them into rough 1/4-inch dice. You can combine the meats in one pile as you chop, but keep the knife moving in a rocking motion so the pieces stay uniform. Chopping by hand is essential here: a food processor will pulverize the meat and release too much fat, turning the sandwich greasy. Look for pieces that are small enough to be scooped up on a fork but still have some texture and chew. The visual cue is a lively mosaic of pink, red, and speckled bits that will distribute evenly throughout the sandwich.

Chop the provolone the same way. Slice the cheese into 1/4-inch thick strips and then across into small dice. The pieces can be slightly larger than the meat, but aim for about the same size so every bite has equal parts meat, cheese, and vegetables. Provolone, especially the sharp aged variety, has a delightfully tangy and nutty flavor that stands up to the salty meats. If your knife starts to stick to the cheese, dip it in warm water or lightly oil the blade. Keep the cheese separate from the meats unless you plan to mix everything immediately; this prevents the cheese from clumping together as it warms.

Prep the vegetables. Shred the iceberg lettuce into thin ribbons and rinse them under cold water, then spin dry in a salad spinner or pat with paper towels until completely dry. Quarter the cherry tomatoes and gently squeeze out the seeds if they are very juicy. Mince the red onion into a small dice, and drain the pepperoncini well on a paper towel before chopping. Wet vegetables are the number one enemy of a make-ahead sandwich. Dry greens and tomatoes create a crisp texture and keep the dressing from thinning out. Put the lettuce aside in a separate bowl, and combine the tomatoes, onion, and pepperoncini in another bowl. This separation is key if you are making the sandwich ahead for work lunches.

In a large bowl, whisk together the Italian vinaigrette, mayonnaise, dried oregano, red pepper flakes if using, and a generous pinch of black pepper. Taste the dressing and adjust the seasoning; remember that the meats and cheese are salty, so avoid adding much salt here. The mayonnaise not only adds creaminess but acts as an emulsifier, helping the oily vinaigrette cling to every chopped surface. Add the chopped meats, cheese, tomatoes, onion, and pepperoncini to the bowl and toss with a spatula until everything is evenly coated. The mixture should look glossy and cohesive but not drenched. Let it sit for five minutes so the flavors meld and the dry bread crumbs can absorb the dressing without turning mushy.

Fold in the lettuce only if you are serving immediately. If you are meal-prepping for work lunches, keep the lettuce separate and store the meat-and-cheese filling in an airtight container in the refrigerator. This is the real secret to a no-soggy, no-reheat work lunch. When you are ready to pack your lunch, spoon the filling into the chilled bread shells, top with the crisp lettuce, and press the halves together. Wrap each sandwich tightly in parchment paper or beeswax wrap. The paper does more than look pretty: it keeps the sandwich compact, helps the bread stay fresh, and allows the flavors to settle. If you prefer, you can also serve the chopped Italian salad in a bowl with bread on the side.

Assemble and enjoy! Unwrap your sandwich, maybe cut it in half on a diagonal so you can see all those beautiful layers of meat, cheese, and vegetables. The texture should be cool, crisp, creamy, and briny all at once, a true deli-style experience. Since this is a cold recipe, there is no reheating step; just grab it from the fridge, or pack it with an ice pack if your lunch bag is warm. For picnics or packed lunches, keep the sandwich chilled right up until serving and consume within a day for the best texture. Pair it with a crunchy dill pickle, some kettle-cooked chips, or a handful of grapes for a balanced work lunch.