In a large skillet melt 2 tablespoons butter over medium heat.
Add chorizo sausage and break up the meat into small bite sized crumbles with a wooden spoon.
Add the diced onion and red bell pepper.
Cook until the Chorizo sausage is cooked through and the onions and bell pepper are tender.
Sprinkle flour over the meat mixture in the pan.
Stir and cook for 1-2 minutes to coat the mixture with the flour and cook off the raw flour taste.
Add salt and pepper to the pan, stir to combine.
Pour in the milk and stir constantly until the sauce mixture thickens, about 5-6 minutes.
Lower the heat to low and add cubed Velveeta and shredded smoked cheddar cheese. Stir until all the cheese has completely melted and the sauce is rich and creamy. Remove the pan from heat.
Stir in the cooked, drained pasta and stir to combine everything.
Serve immediately topped with a generous sprinkle of freshly cracked black pepper.