Sauté the chopped onion in the butter for a few minutes or until translucent.
Add the chicken and vegetables and cook in the pan until done.
Add the rice and toss it until it is heated through.
Add a couple tablespoons of ketchup and toss quickly, just to flavor and color the rice.
Season the mixture with salt and black pepper.
Mound the rice on a plate.
Crack the eggs into a bowl and whisk in salt and pepper.
Pour this mixture into a pan with some butter and cook the omelet until it is done but still slightly runny in the center.
Put the omelet on to the rice or else cut down the middle so the egg runs into the rice a bit.
Serve with some ketchup on top.
