Pat the steak dry and season both sides generously with salt, black pepper, garlic powder, and a light dusting of smoked paprika. Let rest 10 minutes at room temperature.

Bring a large pot of salted water to a boil and cook the tortellini according to package directions until al dente. Reserve 1/2 cup of pasta water, then drain and set aside.

In a large skillet over medium-high heat, add 2 tbsp olive oil. When shimmering, sear the steak 2–4 minutes per side depending on thickness and desired doneness (aim for medium-rare to medium). Transfer steak to a cutting board and tent loosely with foil to rest 5–7 minutes.

Reduce heat to medium and add 4 tbsp butter to the same skillet. Once melted, add the minced garlic and cook 30–45 seconds until fragrant (do not brown).

Pour in 1 cup heavy cream and 3/4 cup whole milk, stirring to combine. Bring to a gentle simmer and let reduce 2–3 minutes until slightly thickened.

Stir in 1 1/4 cups shredded parmesan off heat until melted and smooth. If sauce seems too thick, add a splash of reserved pasta water to reach desired consistency. Taste and adjust salt, pepper, and a pinch of red pepper flakes if using.

Slice the rested steak against the grain into bite-sized strips. Add the drained tortellini and sliced steak to the skillet, tossing gently to coat everything in the cream sauce and warm through for 1–2 minutes.

Sprinkle with chopped parsley and a crack of black pepper. Serve immediately.