In a large (and deep) skillet or sauce/stock pot brown the ground beef.
Add salt and pepper to taste and begin breaking the ground beef down into small crumbles.
Add the chopped onion and cook and stir until ground beef is cooked through and onions are translucent.
Drain any excess fat if necessary and immediately return back to the pan.
Add the tomato paste, seasonings and stir allowing the paste to soften and combined with the beef.
Pour in the canned diced tomatoes and stir one final time.
Add desired noodles on top of the taco meat sauce. Then, pour the beef stock (or water) directly over the noodles.
Pour enough liquid to cover the noodles. Gently pat the noodles if needed to submerge the noodles into the liquid.
Now, cover the pan or pot and simmer the one pot taco spaghetti for at least twenty minutes or until noodles are cooked through and fork tender.
After the noodles have cooked through and fork tender, it is time for the final steps of this delicious recipe.
It is ok to turn the heat to low (or off) because it is just about time to serve.
Sprinkle the assorted cheese on top of the taco spaghetti, cover and allow the cheese to melt.
After the cheese has melted, garnish with sour cream if desired and roughly chopped cilantro.
Serve immediately and with a quick side salad and enjoy!