Cook the noodles according to the package directions for al dente. You really want the noodles to be slightly undercooked (as opposed to overcooked) because they will absorb more moisture while they cook in the slow cooker.

In a large sauce pan, heat the butter over medium heat. Add the garlic and cook for one minute. Now add the cream cheese, 2 cups of the milk and the shredded cheese. Stir until well combined and the cheese begins to melt. Remove from heat.

In a bowl, whisk together the eggs and remaining 1 cup of milk. Add a little bit of the hot, cheesy liquid to this bowl and stir. This will help to temper the eggs so they don't cook too quickly.

Now add everything to a slow cooker. Season with salt and pepper. Give it a stir. Place the lid on top and cook on low for 1 hour.