Season the steak bites by cutting the sirloin steak into about 1-inch cubes and seasoning generously with kosher salt, black pepper, smoked paprika, and garlic powder. Let them sit for 5 minutes.

Heat olive oil and half the unsalted butter in a large skillet over medium-high heat until the butter is melted and shimmering.

Add half of the seasoned steak bites in a single layer and sear for about 3 minutes without moving. Flip and cook for another 2-3 minutes until brown on both sides but pink in the center. Set aside covered with foil.

In the same skillet, add the remaining unsalted butter, melt, then stir in minced garlic and sauté for about 1 minute until fragrant, without burning it.

Pour in beef broth to deglaze the skillet, scraping up browned bits, and simmer for 1-2 minutes.

Stir in heavy cream and bring to a gentle simmer. Cook for an additional 2 minutes to thicken slightly.

Remove from heat and whisk in grated Parmesan cheese until smooth. Adjust thickness with more broth if needed.

Return the seared steak bites to the skillet and stir to coat in the creamy sauce, letting them soak for about 1 minute.

Sprinkle with chopped parsley and red pepper flakes before serving hot with sides such as mashed potatoes or crusty bread.