For the chicken:
Mix the oil, Greek yogurt, whole grain mustard, salt, chopped cilantro, and Limón-Chile in a bowl and whisk together. Pour into a food processor and pulse for 20 seconds to emulsify for a smoother finish.
Cut the chicken into cubes and place into a gallon-sized Ziploc bag. Add the marinade and toss until the meat has been evenly coated.
Place the bag of chicken in the fridge to marinate for at least one hour. (Or overnight!)
Preheat the oven to 400 degrees.
Place the marinated chicken in a glass dish and bake for 10-15 minutes. Alternatively, the chicken can be finished on the grill.
For the bowls:
Cook rice, corn, and black beans per the instructions on each package.
Dress each bowl with spinach, rice, corn, black beans, and tomato. Add chicken. Garnish the top with cheese and cilantro, as desired.