Slice onion, bell pepper, and ham thinly.
Boil spaghetti noodles in boiling water and prepare.
Heat cooking oil in a pan and sauté onion, bell pepper, and ham.
Add the cooked noodles and ketchup, then stir-fry together.
Season with salt and pepper to taste.
Plate the pasta and, if desired, sprinkle parsley powder on top.