In a large pot or Dutch oven, add olive oil and set over medium heat. Once shimmering, add onion and cook for 5 minutes, or until it starts to soften.

Add ground beef, garlic, and taco seasoning and cook, stirring often, until the meat is cooked through, about 5 minutes.

Add the tomato paste and stir to coat all of the meat and vegetables. Add diced tomatoes and stock and bring to a boil. Add pasta and reduce heat to a simmer and cook, stirring occasionally, for about 15 to 18 minutes, or until the pasta is cooked al dente and almost all of the liquid has cooked off.

Remove from heat and stir in the cheese, mixing until melted. Serve with toppings of choice.