Boil and Cook the Pasta: Fill a large pot with water and add salt. Bring to a boil and cook pasta shells according to package instructions until al dente, about 8-10 minutes. Drain and set aside.

Sear the Steak: Season steak with salt and pepper. Heat olive oil in a skillet over medium-high heat. Add steak in a single layer and cook 3-4 minutes per side until browned. Remove and set aside.

Prepare the Garlic Butter: In the same skillet, reduce heat to medium, add butter, minced garlic, and thyme. Sauté for about 1 minute until fragrant.

Combine Steak with Garlic Butter: Return seared steak to skillet with garlic butter. Toss to coat and cook for about 1 minute.

Make the Creamy Sauce: In a clean skillet, melt another tablespoon of butter. Add more minced garlic and sauté for 1-2 minutes. Pour in chicken broth and heavy cream. Simmer for 3-4 minutes, stirring occasionally.

Add Cheese and Seasoning: Stir in Parmesan cheese and Italian seasoning until fully melted and sauce is creamy.

Combine Pasta and Sauce: Add drained pasta shells to the skillet with the sauce. Toss gently to coat.

Final Touch with Steak: Fold in garlic butter steak cubes, combining everything well.

Serve and Garnish: Plate the dish hot, garnishing with freshly chopped parsley and extra Parmesan cheese if desired.