Cook the sausage and onion in a large non stick pan, break up sausage with the spatula. Cook until lightly browned, drain excess fat.
Add the cooked sausage to an ungreased 8x8 inch baking pan.
Cook macaroni in a pot of salted boiling water until just tender, drain.
Place cooked macaroni on top of sausage.
In a saucepan on low heat, mix together soup and milk, heat until hot.
When soup mixture is hot, scoop out a small amount and add to the lightly beaten eggs in a small mixing bowl, and mix together. Then pour the egg mixture back into the soup mixture.
Stir cheese into the soup mixture, stirring until the cheese is melted.
Pour mixture all over the macaroni.
Preheat your oven to 180° C (350° F).
In a small bowl, mix together the crushed corn flakes and butter.
Sprinkle crumb mixture along the edge of the pan.
Bake for 40-45 minutes.
Serve with sides of your choice. Enjoy.