Bring a large pot of salted water to a boil. Add 8 oz of penne pasta and cook according to package instructions until al dente, usually about 10-12 minutes. Drain and set aside.
In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add the minced garlic and sauté for 1-2 minutes until fragrant but not browned. Add the shrimp and cook until they turn pink and opaque, about 3-4 minutes. Season lightly with salt, pepper, and 1 teaspoon red pepper flakes. Remove the shrimp and garlic mixture from heat.
In the same skillet, pour in 2 cups of heavy cream, scraping any flavorful bits off the bottom. Lower the heat and bring the cream to a gentle simmer. Stir in 1 cup grated Parmesan cheese until melted and smooth. Add salt and pepper to taste.
In a large mixing bowl, combine the cooked penne pasta, sautéed shrimp and garlic, 2 cups chopped lobster meat, and 1 cup cooked crab meat. Pour the creamy Parmesan sauce over the mixture and gently toss to coat everything evenly.
Preheat your oven to 375°F (190°C). Transfer the seafood pasta mixture into a greased 9x13-inch baking dish. Sprinkle 1 cup shredded mozzarella cheese evenly over the top.
Bake uncovered for 20-25 minutes until the cheese is bubbling and golden brown. For an extra golden crust, you can broil for an additional 1-2 minutes—just watch closely to avoid burning.
Remove the pasta bake from the oven. Drizzle 1 tablespoon of fresh lemon juice over the top and sprinkle with 2 tablespoons chopped fresh parsley for a bright, fresh finish. Serve hot and enjoy!