Cut steak into 2-3 inch pieces. Mix together smoked paprika, cayenne pepper, onion powder, garlic powder, black pepper, salt, thyme, and oregano to create blackened seasoning. Rub steak pieces evenly with 1-2 tablespoons avocado oil, then season well on all sides with blackened seasoning. Let sit at room temperature for 10-15 minutes.

Peel and quarter potatoes. Place in a bowl of cold water for 10 minutes to remove excess starch. Drain, then place in a large pot of salted water and bring to a boil. Cook until fork tender, about 15-20 minutes.

Heat 2-3 tablespoons avocado oil in a large cast iron skillet over medium-high heat. Add steak pieces without overcrowding (work in batches if needed). Cook undisturbed for 2 minutes until golden brown.

Flip steak pieces once, continue cooking for 1 minute, then reduce heat to low and cook 1 more minute. Remove steak and place in a bowl.

Add 3 tablespoons butter and 1 tablespoon minced garlic to the same pan. Saute until fragrant, about 30 seconds. Return steak to pan and toss in garlic butter, coating all sides. Cook for 1 minute. Remove steak to bowl and tent with foil.

In the same pan, add remaining 2 tablespoons butter and remaining minced garlic. Saute until fragrant. Slowly whisk in heavy cream and bring to a simmer. Let reduce for 3-5 minutes.

Meanwhile, drain potatoes. Add melted butter and warmed half and half. Mash until no longer chunky. Stir in monterey jack cheese, garlic powder, salt, and pepper. Mix until smooth.

Add red pepper flakes, diced green onions, and parmesan cheese to the cream sauce. Whisk until sauce thickens. Taste and adjust salt and pepper as needed.

Plate cheesy mashed potatoes, top with garlic butter steak bites, and generously drizzle with parmesan cream sauce. Serve immediately.