Place the chicken breasts between two sheets of plastic wrap or parchment paper. Using a meat mallet or rolling pin, pound them to an even thickness, about ½-inch each.
In a small bowl, mix the salt, smoked paprika, black pepper, garlic powder, onion powder, chili powder, and cayenne (if using). Season both sides of the chicken evenly.
To a large cast iron or stainless steel skillet over medium-high heat, add olive oil and butter. Once the butter melts and starts to sizzle, add the chicken.
Cook chicken undisturbed for 4-5 minutes until golden brown. Then, flip and cook for another 3-4 minutes on the other side, or until the chicken reaches an internal temperature of 165°F.
Transfer the chicken to a cutting board. Tent loosely with aluminum foil, and let it rest for 5 minutes before slicing.
To a large salad bowl, add the chopped romaine. Top the lettuce with sliced cooked chicken, cherry tomatoes, shallot, corn, black beans, avocado, shredded Monterey Jack cheese, jalapeño, and crispy bacon.
Drizzle with Cowboy Butter Ranch Dressing. Toss gently to coat.
Scatter croutons on top. Garnish with sliced jalapeños.
Serve with lime wedges for squeezing over the salad.