Marinate time required, but overlap by making the sauce in the meantime. Recipe from Brian Murray posted on The Pioneer Woman's site sponsoring her Bush’s Grillin’ Beans/Pioneer Woman Recipe Contest.
Pound the chicken breasts until approximately 1/2 inch thick. Sprinkle on 2 Tablespoons of the taco seasoning and rub into the meat. Melt 2 Tablespoons of the butter, pour on chicken breasts, and mix together. Place in refrigerator to marinate for 1 hour. Grill chicken for 4 minutes on each side over high heat. Remove from grill and let rest.
Brown chorizo over medium heat and break into pieces. Remove chorizo from pan, but leave any remaining grease. Reduce heat to medium low and add 2 Tablespoons of butter. Add onion, bell pepper, and garlic to pan. Saute until translucent. Add chipotle pepper and 1 Tablespoon of adobo sauce to pan. Cook 5 minutes, stirring frequently. Add cream and 2 Tablespoons taco seasoning to mixture and cook for another 5 minutes. Pour mixture into blender (or with immersion blender), blend until smooth. Transfer contents back into pan, add chorizo to mixture, and cook for additional 5 minutes.
Slice chicken into strips and pour 1/4 of sauce on each breast.