**Cook the Ground Beef:**
- Heat a large skillet or Dutch oven over medium heat. Add ground beef and onion, cooking until the beef is browned and the onion is softened. Drain excess fat if necessary.
**Add Garlic and Seasoning:**
- Stir in minced garlic and taco seasoning. Cook for 1-2 minutes until fragrant.
**Build the Sauce:**
- Add diced tomatoes, tomato sauce, and beef broth. Stir to combine, then bring to a simmer.
**Cook the Pasta:**
- Stir in the broken spaghetti. Cover and simmer for 12-15 minutes, stirring occasionally, until the pasta is tender and the sauce has thickened.
**Add Cheese:**
- Remove the skillet from heat and stir in half of the shredded cheese until melted. Sprinkle the remaining cheese over the top, cover, and let it melt for 2-3 minutes.
**Serve:**
- Garnish with your favorite toppings like green onions, cilantro, or a dollop of sour cream. Serve hot!