Begin by bringing a large pot of salted water to a rolling boil. Carefully add the jumbo pasta shells and cook until al dente, about 10-12 minutes. Drain and spread them on a baking sheet to cool.

Preheat your oven to 350°F (175°C). Position the oven rack in the center.

In a large mixing bowl, combine the ricotta cheese, pumpkin puree, grated Parmesan cheese, egg, nutmeg, kosher salt, pepper, garlic powder, and minced fresh sage. Blend until smooth.

In a separate bowl, combine the remaining pumpkin puree with the jarred vodka sauce and heavy cream. Stir until smooth.

Spread approximately 3/4 of the prepared sauce mixture evenly across the bottom of a 9x13 inch baking dish.

Using a tablespoon, scoop about 2 tablespoons of your creamy filling and gently stuff each shell. Place the filled shells seam-side up on top of the sauce.

Cover the baking dish with aluminum foil and bake for 30 minutes.

Remove the foil and sprinkle the shredded mozzarella cheese evenly over the shells. Bake uncovered for an additional 15 minutes or until the cheese is melted and bubbly.

For a crispy finish, switch the oven to broil for an additional 1-2 minutes, keeping a close eye to avoid burning.

Remove the dish from the oven and let it cool for a few minutes before serving. Serve hot.