In a large skillet, heat the olive oil over medium heat. Add the diced onion and sauté for about 3-4 minutes, or until softened and translucent. Stir in the minced garlic, cooking for an additional 30 seconds until fragrant, ensuring it doesn’t burn.

Add the ground beef to the skillet, breaking it apart with a spatula. Cook for 5-6 minutes, stirring occasionally, until the meat is browned and no longer pink. If there's excess fat, drain it carefully.

Stir in the taco seasoning, tomato sauce, and diced tomatoes. Mix everything thoroughly, allowing the flavors to combine for about 1-2 minutes.

Pour in the beef broth and add the rotini pasta to the skillet. Stir to combine all ingredients, ensuring the pasta is submerged. Increase heat to bring the mixture to a boil.

Once boiling, reduce heat to low and cover the skillet with a lid. Allow the pasta to simmer for 12-15 minutes, stirring occasionally until the pasta is tender and most of the liquid is absorbed.

Remove from heat and sprinkle in the shredded cheddar cheese. Stir gently until the cheese is fully melted and incorporated.

Garnish with fresh cilantro, a dollop of sour cream, or sliced jalapeños if desired. Serve hot.