Cook the rice according to package instructions and set aside. Roast the Poblano peppers by putting them on a pan under your oven broiler. Keep a good eye on them and rotate them so they blacken on all sides. Transfer them to a plastic food storage container while you chop and prep the onions, peppers, and garlic. When they are cool enough to handle, peel the skin from the outside of the peppers so that most of the charred part is off of the pepper. Chop the peppers once the skin and seeds are removed (See NOTES in this recipe if you wish to skip this step)
Saute the vegetables until they are softened. Add the rice, beans, cumin, chili powder, salt (to taste) and top with cheese. Transfer to a 400 degree oven for 10 minutes until the cheese is melted and the edges are golden.
Serve with your favorite salsa, guacamole or sour cream.
If you don't want to roast the poblano peppers fresh, you can use a 4 oz. can of roasted diced chilies.