No panini press needed: For the easiest Italian lunch, crusty bread, good cheese, and a couple of cans will do just fine.
In a small bowl, whisk together mustard and oil until thick; spread on bread. Layer bottom half of bread with some of the lettuce, then cheese, tomatoes, and parsley. Season with salt and pepper. Top with remaining lettuce and bread.
Wrap sandwich tightly in plastic; place on a baking sheet. Top with another sheet, and weight down with canned goods or a heavy skillet. Refrigerate at least 1 hour and up to overnight to meld flavors. Cut in half, and serve.
Look for ciabatta bread, bagged or in bins, at the deli or in the bakery section. Its floured, crusty exterior and dense interior are just right for pressed sandwiches.