Preheat your oven to 350°F (175°C). Grease a 9-inch (23 cm) pie dish or baking dish with butter.
In a large pot of boiling salted water, cook the elbow macaroni according to package instructions until al dente. Drain and set aside.
In a large bowl, whisk together the eggs, milk, and heavy cream. Stir in the grated cheddar cheese, Parmesan cheese, chopped onion, bell pepper, thyme, paprika, black pepper, and salt.
Add the cooked macaroni to the cheese mixture and mix until well combined.
Pour the macaroni mixture into the prepared pie dish. Smooth the top with a spatula. If desired, sprinkle breadcrumbs on top for a crunchy finish.
Bake in the preheated oven for 30-35 minutes, or until the top is golden brown and the pie is set in the center.
Let the pie cool for a few minutes before slicing and serving.
Enjoy your meal!