In a large skillet over medium heat, add the ground beef and chopped onion, cooking for about 5–7 minutes or until the meat is browned and fully cooked. Stir occasionally to break up the meat and ensure even cooking. Once done, drain any excess fat to keep your One-Pot Taco Spaghetti from being greasy.

Sprinkle the taco seasoning over the beef mixture, stirring well to coat all the meat with those zesty flavors. Cook for another 1–2 minutes, allowing the seasoning to toast slightly.

Pour in the can of diced tomatoes, beef broth, and frozen corn into the skillet. Stir everything together and bring to a boil.

Add the spaghetti to the boiling mixture, ensuring the noodles are fully submerged. Reduce heat to low and cover. Let it simmer for 12–15 minutes until the spaghetti is tender.

Remove from heat, sprinkle the shredded cheddar cheese on top, cover again for a few minutes to melt the cheese.

Scoop into bowls, garnishing with the chopped green bell pepper and black olives if desired. Serve warm.