Start with a pot of salted water. Boil the spaghetti until just al dente—about a minute less than the package says. Drain it and set it aside. It’ll cook a little more when we mix it with the sauce, so you don’t want it too soft now.
In your skillet, brown the ground beef over medium-high heat. Break it apart as it cooks—this takes about 5–7 minutes. Once it's no longer pink, drain the grease if needed. Add your taco seasoning and stir well to coat every bit of the meat. Then pour in the diced tomatoes (with juices) and tomato sauce, mixing it all together.
Next, pour in the broth and bring it to a light simmer. This step helps develop flavor and creates the saucy base. When it’s bubbling, add the cooked spaghetti and gently toss everything so the pasta soaks up that taco goodness.
Once combined, sprinkle the shredded cheddar evenly over the top. You can let it melt on the stovetop with the lid on, or pop the whole skillet (if oven-safe) into a 375°F oven for 10 minutes. That bubbly, cheesy finish is so worth it!
When it's hot and cheesy, it’s time to garnish. I love topping it with sour cream and a handful of chopped cilantro or green onions. It adds freshness and a little tang. Serve it up warm and enjoy every bite.