Boil water in a large pot.
Add elbow macaroni and cook according to package instructions.
Drain the macaroni and set aside.
In the same pot, combine milk and Velveeta cheese over medium heat.
Stir until the cheese is melted and the mixture is smooth.
Add salt, pepper, garlic powder, and onion powder.
Return the cooked macaroni to the pot.
Stir until the macaroni is well coated in the cheese sauce.
Add butter and mix until melted and combined.
Serve warm, garnished with parsley if desired.