Step 1

Thinly shave the chicken breast across the grain into shavings. Use a sharp knife to create thin slices.If you’re having trouble, you can firm up the chicken breast in the freezer for around 15 minutes to make it easier to slice.Begin preheating a griddle or cast iron pan over medium heat.Add the sliced chicken to a bowl, then add the mayo, salt, and remaining spices. Use your hands to massage the mayo and spices into the chicken so everything is evenly coated and seasoned.

Step 2

The griddle or pan should be smoking hot by now. If not, turn up the heat. Spread the mayo-marinated chicken onto the griddle. Use a spatula to create an even layer across the cooking surface.Don’t overwhelm the pan. If needed, do this in multiple batches so that everything can properly sear and develop color.Once the underside of the chicken has browned, flip the chicken over. Allow the pieces to finish cooking through and get color on other sides. Turn off the heat.

Step 3

If needed, slice the bread. Optionally scoop out some of the bread from the inside of the roll to create more room for the fillings.Add the slices on top of the cooked chicken on the pan. The residual heat will steam and warm them through.In the meantime, prep or gather remaining sandwich components or cleanup other items.

Step 4

To assemble: Add a slathering of mayo to the inside of the buns (this creates a protective fat barrier that prevents the bread from becoming soggy). Layer in the tomatoes, a sprinkle of dried oregano, the lettuce and pickled pepperoncini peppers, a small grating or parmesan, and a splash of balsamic. Then add a serving of cooked chicken. Finish with extra grated parm and balsamic vinegar on top, then close with the top bun.Tightly wrap the sandwich in foil or parchment paper. This will help the sandwich steam and soften a bit, and keep the fillings contained during eating. Enjoy.