Heat the vegetable oil in a large skillet over medium heat. Add the diced onion and cook for 3 to 4 minutes until it softens. Stir in the minced garlic and cook for 30 seconds more.
Add the uncooked rice to the skillet and stir to coat it with the oil. Cook for 1 minute. Sprinkle in the chili powder, cumin, smoked paprika, cayenne, and salt, then stir for another 30 seconds to toast the spices.
Pour in the drained black beans, the can of diced tomatoes with green chilies, and the water. Stir everything together and bring the mixture to a boil. Reduce the heat to low, cover the skillet, and simmer for 18 to 20 minutes until the rice is tender and most of the liquid has been absorbed.
Remove the lid and fluff the rice with a fork. Sprinkle with chopped cilantro and serve with lime wedges on the side.