Drizzle oil into a large pot of boiling salted water Add the pasta and cook according to the directions on the package, 6 to 8 minutes. Drain well.

Meanwhile, heat the milk in a small saucepan, but don’t boil it. In a large pot, melt 6 tablespoons of butter and add the flour. Cook over low heat for 2 minutes, stirring with a whisk. Still whisking, add the hot milk and cook for a minute or two more, until thickened and smooth. Off the heat, add the Gruyere, Cheddar 1 tablespoon salt, pepper, and nutmeg. Add the cooked macaroni and lobster and stir well. Place the mixture in baking dish or individual gratin dishes.

Melt the remaining 2 tablespoons of butter, combine them with the bread crumbs, and sprinkle on top. Bake for 30 – 35 minutes, or until the sauce is bubbly and the macaroni is browned on the top.