In a large skillet, brown the ground beef completely.
Drain any fat and add in the onion and garlic. Stir about 30 seconds to a minute on medium-high heat.
Add in one cup of water, and taco seasoning. Stir well and then add in the pasta.
Bring to a boil and then lower to low-medium heat and cover the skillet with a lid.
Simmer for about 5-7 minutes and then add in the last cup of water, stirring occasionally. Return the lid and simmer until pasta is tender (about another 5-7 minutes), stirring occasionally.
Remove from heat and sprinkle cheese over the top. Let melt and serve immediately.