Preheat the oven to 375°. Lightly grease a 10-inch cast-iron skillet.
In a large pot of salted boiling water, cook the bucatini until al dente. Drain and run under cold water to stop the cooking. Drain well.
In a large bowl, whisk together the butter, eggs, cheese, cream, parsley, olive oil, garlic, pepper and salt. Add the pasta and toss to coat thoroughly. Scrape into the prepared skillet and bake for about 30 minutes, until just set. Remove from the oven.
Preheat the broiler. Broil the bucatini pie 6 inches from the heat until golden, about 5 minutes. Transfer to a rack and let cool for 10 minutes before cutting into wedges. Serve with warm marinara sauce.
The pie can be kept at room temperature for 4 to 6 hours before serving.
To go with this rich pasta pie, try a zesty Vermentino wine.