Whisk all of the Spice Mix seasonings together in a small bowl. Remove 2 tablespoons to use on the potatoes. While the steak is still on the cutting board, pat it dry and sprinkle with remaining Spice Mix. Toss to evenly coat; set aside.
Place potatoes and 1/3 cup water in a microwave-safe dish. Cover and microwave on high for 6-7 minutes (potatoes should barely be fork tender). Drain and pat dry. Drizzle potatoes with 1 tablespoon olive oil and season with reserved 2 tablespoons Spice Mix. Stir to evenly coat.
Heat 1 tablespoon olive oil in a 12-inch cast iron skillet over medium heat. Once hot, add potatoes and cook undisturbed for 1-2 minutes or until starting to char, then stir potatoes for 1-2 additional minutes until fork tender. Remove to a plate and tent with foil; wipe out skillet.
Heat 2 tablespoon vegetable oil in the now empty skillet over medium-high heat. Once hot, add half of the steak to the skillet in a single layer and let sear undisturbed for 2 minutes, then stir the steak and continue to cook for an addition 1 minute or until steak reaches desired doneness. Remove to a plate; wipe out skillet if there are any black bits.
To then now empty skillet, heat 2 tablespoon vegetable oil over medium-high heat. Once hot, add remaining steak to the skillet in a single layer and let sear undisturbed for 2 minutes. Stir the steak then immediately add butter, garlic, parsley, oregano and thyme. Cook, while stirring for 1 minute then remove from heat.
Add the steak and potatoes back to the skillet and stir to evenly coat in the butter sauce. Season with additional salt and/or pepper to taste. Serve immediately.