Cook pasta in salted water for about 3 minutes less than the recommended time. Drain, rinse with cold water and set aside.

Heat small amount of oil in bottom of an oven safe pot. Add diced andouille sausage, and cook until done. Remove and reserve the andouille.

Using the same pot you used to cook andouille, melt the butter, then add the flour and stir constantly until you get copper or darker roux (approximately 7-9 minutes or when the roux smells nutty). Add diced onions, celery, bell pepper, and jalapeno near end.

Meanwhile, heat the milk and heavy cream in another pan on low-medium heat.

Once roux is finished, slowly whisk in the milk and cream mixture and continue to simmer until the mixture thickens and begins to bubble. Reduce temperature to low and cook another 10–15 minutes. Whisk in the salt and shredded cheeses. Taste and season with additional salt and pepper, if desired. Using an oven-safe baking dish, stir in cooked pasta.

Top with bread crumbs and place entire in a 450° oven until breadcrumbs turn golden brown (approximately 25 minutes).