How to Make It
In a large saucepan, melt the butter in the olive oil. Add the onion and garlic and cook over moderately high heat until softened, about 3 minutes. Add the cumin and cook until fragrant. Add the rice and stir until evenly coated with fat, about 30 seconds. Gently stir in the chiles and beans. Add the water and salt and bring to a simmer. Cover and cook over low heat until the water is absorbed, about 15 minutes. Remove from the heat and let stand, covered, until the rice is tender, about 5 minutes. Gently fluff the rice with a fork, being careful not to break up the beans.