Add all marinade ingredients to a blender cup or food processor and blend until smooth. Marinade will be thick like a paste. Add the marinade and the chicken breasts to a gallon size zip top bag and mix so that all of the chicken is coated. Refrigerate for 2 hours.
Preheat griddle until it reaches about 375 degrees F.
Add about 1 tablespoon of cooking oil to the griddle and spread it around with your spatula. Add drained Southwest corn to the heated oiled griddle in a thin layer. Allow the corn to char and toast a bit (about 4-5 minutes). Then, add the warm corn to a medium bowl with black beans, juice of 1 lime, diced jalapeno, chopped cilantro, and crumbled Cotija cheese. Mix well to combine and set aside.
Make the avocado ranch dressing by combining all dressing ingredients in a blender cup. Blend until smooth, then refrigerate until ready to serve.
Add about 1 tablespoon of your favorite cooking oil to the heated griddle surface and spread it around with your spatula. Place the marinated chicken breasts on the oiled griddle, making sure that each breast is fully in contact with the griddle surface.
Cook the chicken breasts on the first side until about half-way cooked through and a nice crust develops (about 5 minutes). Flip chicken to the second side and continue to cook until done. After about 4-5 minutes, use an instant read probe thermometer to probe each piece of chicken, and remove each piece when it reaches 165 degrees F internal temp. Transfer cooked chicken to a cutting board to rest.
While chicken is cooking on the griddle, add the sliced bell peppers and onions to the griddle. Saute until done to your liking. *I cooked mine to a "tender crisp" since I was adding them to a salad bowl.
After about 10 minutes of rest time, slice the chicken breasts against the grain.
Make your Southwest chicken bowls. Start with a bed of chopped romaine lettuce (or cooked rice). Add the black bean and corn salad and the sautéed peppers and onions. Top with sliced chicken and the avocado ranch dressing. Add your favorite Mexican toppings (salsa, diced tomatoes, sour cream, pico de gallo, etc) and serve.