In a bowl, mix together the smoked paprika, chili powder, dried oregano, onion powder, cayenne pepper, black pepper, sea salt, and garlic powder. Set aside.
Generously sprinkle the Cajun seasoning all over the NY strip steak. Transfer the seasoned steak to a plate and refrigerate uncover for 30 minutes - 1 hour.
In the meantime, prepare the liquid marinade. In a large bowl (in which the steak could fit), whisk together the following ingredients: brown sugar, bourbon, minced garlic, olive oil, gain mustard, soy sauce, red pepper flakes, teaspoon of cajun seasoning blend, and thyme. Save half of the marinade for later.
Next, add the steaks to the large bowl. Cover the bowl with plastic wrap and refrigerate for a minimum of 30 minutes or up to 6 hours. The longer......the better!
Heat up a large cast iron skillet. Remove the steak from the marinade and season all sides with kosher salt and freshly ground black pepper. Cook the steaks for roughtly 3-4 minutes per side or until the steak reaches 135 degrees F (for medium-rare).
Rest the Cajun bourbon steak, while preparing the cajun butter sauce. With the reserved marinade place into a saucepan and bring to a rapid boil. Reduce the heat to a medium-low and continue to cook the sauce until it begins to thicken. Lastly, whisk in the unsalted butter and then remove from the heat.
Slice the steak. Pour the cajun butter sauce over the steak. Garnish with dried parsley and serve immediately.