Preheat the oven to 425°F. Lightly grease a 9x13 inch baking pan with butter or oil. Combine the rice, cumin, and salt in the pan and stir to distribute the spices. Spread in an even layer. Pour in the boiling water.
Cover the pan tightly with heavy duty aluminum foil, sealing all the edges. Bake the rice for 20 minutes. Remove from the oven and stir. If most of the water has not been absorbed, bake uncovered for an additional 3-5 minutes.
Remove from the oven and let rest for 3-5 minutes. Fluff the rice with a fork, drizzle with lime juice, and sprinkle with the cilantro. Stir to combine. Serve with additional lime wedges, if desired.