Preheat the Oven and Prepare the Gratin:
Preheat the oven to 400°F (200°C). In a medium bowl, combine ricotta, pear, and heavy cream. Season with salt and pepper and set aside.

Cook the Conchiglioni:
Boil salted water in a large pot and cook conchiglioni for 2-3 minutes less than package instructions, until not quite al dente. Drain and rinse under cold water to stop the cooking process.

Prepare the Gorgonzola Sauce:
Melt butter in a saucepan over medium-low heat. Whisk in flour and cook for 1 minute. Gradually add warm milk, whisking constantly until the sauce thickens. Stir in gorgonzola and parmesan cheese until melted and smooth. Season with salt and pepper.

Assemble the Gratin:
Stuff the cooked conchiglioni with the ricotta-pear mixture. Spread some gorgonzola sauce in a baking dish or cast iron pan. Arrange stuffed shells and pour remaining sauce over them. Sprinkle with parmesan. Bake for 10-15 minutes or until al dente. Optionally, broil for 2-3 minutes for a golden, bubbly top.

Cook the Filet Mignon:
Season steaks generously with salt and pepper. Heat vegetable oil in a skillet or cast iron pan over medium-high heat until smoking. Sear steaks for 2-3 minutes per side. Remove from the pan when the internal temperature reaches 135°F for medium-rare. Cover with foil and rest for 5 minutes.

Serve:
Let the gratin rest for 5 minutes after baking. Serve filet mignon alongside the pear and ricotta conchiglioni gratin, topped with remaining gorgonzola sauce.