Spray a slow cooker (4 to 6-quart capacity) with cooking spray. Cook the pasta to al dente and drain. Place the macaroni in the slow cooker, immediately add the butter and stir until melted.
Add the evaporated milk, half & half, whole milk, 3½ cups of the cheddar cheese, the Velveeta, salt and pepper; stir to blend well.
Cover and cook on low for 2 to 3 hours. During the last 15 minutes of cooking, sprinkle with the remaining ½ cup of cheddar cheese. Once done, turn the slow cooker setting to warm until ready to serve. Leftovers can be stored in an airtight container in the refrigerator for up to 4 days.
[adthrive-in-post-video-player video-id="0dlbdOjI" upload-date="Mon Jun 26 2017 11:45:00 GMT+0000 (UTC)" name="Slow Cooker Macaroni and Cheese" description="An easy recipe for macaroni and cheese in the crock pot!"]
The previous version of this recipe called for 12 ounces of pasta. Since standard boxes of pasta come in 16 ounces, I adjusted the recipe to account for this amount of pasta.
I do not recommend added uncooked pasta to the slow cooker, as it could absorb too much liquid and become mushy.