Preheat oven to 350°F.
Liberally sprinkle both sides of steak with Tajin seasoning and allow to rest at room temperature for 30 minutes.
Coat a cast iron or skillet of choice with cooking spray. On high heat, sear the meat on each side until golden brown, about 1 minute per side.
Place in oven for 10-30 minutes, depending on the thickness of the steak. Once desired temperature is reached (see note below) let steak sit at least 10 minutes before slicing.
Spray a separate skillet with cooking spray and saute cauliflower rice with salt, pepper and garlic powder until soft.
Slice steak and serve over "rice."
Garnish with fresh cilantro and salsa.