In a large skillet, brown beef and onion for about 5 minutes until beef is cooked through. Season with salt and pepper.
Add in canned diced tomatoes with juices, tomato sauce, chicken broth, 2 cups water, ketchup, dijon mustard, pasta, and bring to a boil over medium high heat.
Cover and reduce heat to low and simmer until pasta is cooked and tender. About 20 minutes.
Temove from heat, stir in cheese and cover to let set and thicken for 5 minutes.
Serve with green onions and quartered cherry tomatoes on top.
Enjoy!