Start by browning the hamburger with the onion, green pepper and mushrooms. ( I use a lid to get the peppers and onions soft).
Next, after the meat is brown, the onion and green peppers are soft and the mushrooms have cooked, add the ketchup and tomato juice.
Break your spaghetti noodles into thirds, add and stir GENTLY into the sauce.
Cover and cook stirring about ever 5-10 minutes for about 30-45 minutes, or until the noodles are done.
HINT: You may want to start off by not using all the tomato juice from the can. I usually find that the more noodles you use the more juice you need. I like mine filled with noodles so I always use much more.