Start by bringing a large pot of salted water to a boil. Once boiling, add the penne pasta and cook until just al dente, about 8-10 minutes. Drain and set aside in a large mixing bowl.

In a large skillet, heat olive oil over medium-high heat. Add the thinly sliced flank steak, seasoned with salt and pepper, and cook for about 3-4 minutes until browned. Add minced garlic and sauté for another minute until fragrant, then remove from heat.

In a mixing bowl, combine cream cheese, sour cream, grated Parmesan cheese, and Italian seasoning. Stir until creamy and smooth. Fold in fresh spinach and drained artichoke hearts gently.

Add the sautéed steak mixture to the creamy sauce, combining thoroughly. Incorporate the cooked penne pasta, tossing gently until every noodle is coated in the sauce.

Preheat your oven to 375°F (190°C). Grease a baking dish. Transfer the pasta and sauce mixture into the dish, spreading evenly. Top with shredded mozzarella cheese.

Place the assembled dish in the preheated oven and bake for 20-25 minutes, until cheese is bubbly and lightly golden on top.

Allow the dish to cool for about 5 minutes before serving. Serve with a green salad or warm, crusty bread.