Preheat oven to 325°F.
Season both sides of the steak with salt and pepper.
Place a large cast iron skillet over medium high heat.
Add 1 tablespoon butter and 1 tablespoon oil.
When butter is melted and mixture is hot and shimmering, place steak in skillet. Cook for 5 minutes on the first side. Flip steak over.
Immediately transfer skillet to preheated oven. Cook for 5 more minutes.
Remove from the oven and set aside to rest.
Prepare pasta according to package directions. Drain. Set aside.
Place another large skillet over medium high heat.
Add remaining 1 tablespoon butter and 1 tablespoon oil.
When butter is melted and mixture is hot and shimmering, add shallot and garlic. Cook until softened, about 2 minutes.
Stir in mushrooms. Cook, stirring often, until they have browned, about 8 minutes.
Add cream. Lower the heat. Simmer until sauce is reduced and thickened, about 10 minutes.
Stir in 3/4 cup Parmesan and sun-dried tomatoes.
Stir in cooked pasta and parsley. Stir and heat until heated through and evenly combined.
Slice prepared steak into thin slices on an angle.
Add steak to pasta. Stir and heat until heated through and evenly combined.
Sprinkle with parsley and remaining Parmesan.
Serve hot.