Melt butter in a skillet over medium heat, add flour and make a blonde roux. Once the roux is set, add onions and saute for 5 minutes.
Whisk in the salt, pepper, and Creole seasoning.
Slowly add the half-and-half and evaporated milk, keep a constant whisk.
Add the Velveeta cheese and hot sauce; whisk until the cheese is melted and smooth. Cook the sauce until it's thick, about 15 minutes.
While the sauce is thickening, cook the noodles and preheat the oven to 450 degrees.
Once the noodles have cooked, add the cooked macaroni to the sauce and combine making sure that the noodles are well coated with the sauce.
In a greased 9 x 13 pan, pour in the macaroni mixture. Cover with the shredded cheddar cheese and cook for about 10 minutes, until it is bubbly and golden.
Garnish with chopped green onions and serve. Enjoy!