Place a medium pot over medium-high heat with the stock or water and brown rice. Season with salt and pepper, and bring up to a bubble. Cover the pan, reduce the heat to low and simmer until the rice has absorbed all the liquid, about 25 minutes. Fluff the rice with a fork.
While rice is cooking, place another pot over medium heat with 1 turn of the pan of EVOO, onion, garlic, jalapeño, salt and ground black pepper. Cook until tender, about 3-4 minutes. Stir in cumin and cook about 1 minute then add tomatoes and beans, and heat through, about 2 minutes. Keep warm until the rice is ready.