In a large skillet or pot, sauté the onions in two tablespoons of olive oil over medium heat. Season the chicken with salt and pepper.
Once the onions soften, increase the heat to medium-high and add the chicken to the pan.
Brown the chicken pieces and add the garlic. Cook for about 1 more minute.
Push the chicken to one side of the pan and add an additional tablespoon of olive oil to the other side.
Add the uncooked rice to the olive oil and saute it for a couple of minutes.
Add the enchilada sauce, diced tomatoes, water, and cumin. Stir to combine. Bring mixture to a boil, then lower the heat to a simmer and cover the pan with a tight-fitting lid.
Cover the pan. Cook the chicken and rice mixture, making sure to stir every once in a while, for about 15 minutes or until the rice is tender and the liquid is absorbed.
Sprinkle cheese on top and cover the pan with a lid, letting it sit for 1-2 minutes or until the cheese has melted.
Serve, sprinkle with desired toppings, and enjoy!