Heat the olive oil in a dutch oven or large enough skillet with a lid over medium heat to medium-high heat. Add the onions and cook for about 4-5 minutes or until translucent. Make sure to adjust the heat so they do not burn.
Add the ground beef to the onions and cook while breaking them apart.
Add the Mexican homemade blend or store-bought spices to the pan and continue to cook until no longer pink. You will want to drain any excess fat from the pan before moving to the next step.
Pour in the pasta sauce, Ro-tel, and water and bring to a boil.
Once the sauce has come to a boil, you can add the half-length spaghetti to the skillet and reduce it to medium heat.
Cook the pasta according to the package stirring frequently. I suggest cooking the pasta in the sauce until it is al dente. Overcooking the spaghetti can make this recipe mushy.
Once the pasta is ready, add half of the cheese and mix until melted.
Move the pasta into a large bowl and sprinkle the remaining cheese on top.
Garnish with chopped cilantro (optional)