Brown the ground beef and onions in a Dutch oven or large pot over medium-high heat. Cook until the ground beef is browned and the onions are soft.
Add the garlic, stir together and cook for 1 minute.
Add in the Rotel tomatoes, tomato sauce, taco seasoning, beef broth, tomato paste, and Worcestershire sauce. Bring the mixture to a boil.
Add in the spaghetti noodles. Reduce the heat to medium, simmer and cook until the spaghetti is tender, approximately 15-18 minutes. Scrape the bottom of the pot several times and stir frequently while cooking.
With about 5 minutes of time left, stir in the cheese and let it melt.
Remove from heat, top with chopped cilantro if desired and serve immediately.