Pour the La Lechonera Natural Mojo marinating sauce in a dish or ziplock bag and marinate the chicken for at least 1 hour, up to 4 hours.
In a medium saucepan, melt the butter on medium heat.
Add the onion, bell pepper, and Kosher salt. Cook for about 6 minutes, or until onion is tender.
Add the garlic. Stir and cook for about 30 seconds.
Stir in the canned tomatoes and the juice, then mash with a potato masher.
Turn up the heat to high and bring to a boil. Once boiling, reduce the heat to medium and simmer until slightly thickened. Should take about 10 minutes.
Off heat, stir in the Parmesan cheese, basil, olive oil, and 1/4 teaspoon of pepper.
Remove the chicken from the marinade. Discard the marinade.Pat the chicken cutlets with a paper towel, so to create a dry cooking surface.
Turn on the grill and set to medium heat. Clean grill with brush and baste on vegetable oil
Lightly season the chicken with salt and pepper.
Grill chicken on the first side until well-browned, for about 3 minutes.
Flip chicken over and add 2 Tablespoons of the cooked tomato mixture to each cutlet, spreading on top of the cooked side.
Close grill and cook chicken for another 3-5 minutes or until it registers about 155ºF.
Top chicken cutlets with shredded mozzarella, then cook till cutlets reach 160ºF.
Remove chicken from the grill, tent with foil, and allow to rest for 5 minutes before serving.
Any remaining tomato sauce can be served on the side.