Let’s embark on a culinary adventure together, step by step, to create this delightful dish:

1. Preheat your oven to 375°F (190°C).
2. Cook the jumbo pasta shells according to package instructions until al dente. Drain and set aside.
3. In a large skillet, heat the olive oil over medium heat. Add the chopped mushrooms and cook for 5-7 minutes until they release their moisture and become golden brown.
4. Add the minced garlic to the mushrooms and sauté for another 2 minutes until fragrant.
5. In a large bowl, combine the cooked mushroom-garlic mixture, ricotta cheese, Parmesan cheese, parsley, oregano, salt, and pepper. Mix until well combined.
6. Fill each cooked pasta shell with the mushroom-cheese mixture and place them in a greased baking dish.
7. In the same skillet used for the mushrooms, add the heavy cream and vegetable broth. Bring to a simmer and let it reduce slightly, about 5 minutes.
8. Pour the creamy mixture over the stuffed shells in the baking dish.
9. Sprinkle the shredded mozzarella cheese over the top.
10. Bake in the preheated oven for 20-25 minutes, or until the cheese is bubbly and golden.
11. Garnish with fresh basil before serving, if desired.