In a microwave-safe bowl, microwave the chopped onion for about two minutes or until tender. Drain excess liquid.
Mix the elbow macaroni, shredded cheddar cheese, and minced fresh parsley with the cooked onion.
Blend the evaporated milk, cottage cheese, Dijon mustard, salt, and pepper in a blender or food processor until smooth.
Stir everything together until the macaroni mixture is well combined with the creamy mixture from the blender.
To prevent sticking, grease two (1 1/2-quart) baking dishes.
Make sure the macaroni and cheese mixture is evenly distributed in the greased baking dish.
Set your oven to 350 degrees Fahrenheit (175 degrees Celsius).
Bake the baking dish, uncovered, for about 20 to 25 minutes, or until the top turns golden brown.
Let the mac and cheese cool for a few minutes after removing from the oven.
Make your own homemade Olive Garden mac and cheese and enjoy!