Preheat the oven to 325 degrees F. Grease and ovenproof casserole dish.

In a saucepan over medium heat, melt 1 Tbsp of butter and add onion, shallot, and garlic. Cook for 2 minutes. Add the peppercorns, heavy cream, and half-and-half. Decrease the heat to low and simmer for 10 minutes. Strain the mixture through a fine strainer and discard vegetables.

In the same saucepan over medium heat, melt 3 Tbsp of butter, add flour, and whisk into the butter. Continue to stir, cooking for about 2 minutes until the flour changes to beige color. Slowly add cream mixture, whisking constantly, and cooking until the mixture thickens, approximately 5 minutes. Remove from the heat and stir in the cheeses until smooth. Season with salt and pepper and set aside. Add lobster if using.

Cook pasta until al dente in a large pot of salted boiling water.

While the pasta is cooking, in a saute pan over medium-high heat, melt 2 Tbsp of butter, add panko, and saute until the panko is golden-brown, about 3 minutes. Remove from the heat and add the parsley and chives and mix well.

Drain the pasta and save 1/2 cup of the cooking water. Transfer pasta to a large bowl and pour sauce over the pasta. With a wooden spoon, stir well to ensure that sauce gets into the tubes of pasta. Thin with pasta water if necessary.

Place the pasta into prepared casserole dish. Top with panko mixture. Bake for 12 to 15 minutes or until heated through.

When heated-through, remove from oven, poke holes all over casserole with knife, and drizzle in the truffle oil. Let sit for 2 minutes and serve.