Heat the olive oil in a large skillet over medium heat. Add the chopped onion and cook until softened, about 5-7 minutes.
Add the minced garlic and cook for another minute until fragrant. Be careful not to burn the garlic.
Add the chicken pieces to the skillet. Season with smoked paprika, cumin, cayenne pepper (if using), salt, and black pepper. Cook, stirring occasionally, until the chicken is browned on all sides.
Stir in the rinsed black beans, diced tomatoes (with their juice), vegetable broth, and rinsed quinoa. Bring the mixture to a simmer.
Reduce the heat to low, cover the skillet, and let it simmer for 15-20 minutes, or until the quinoa is cooked and the liquid has been absorbed. Stir occasionally to prevent sticking.
Once the quinoa is cooked, remove the skillet from the heat. Stir in the fresh cilantro and lime juice.
Taste and adjust seasoning if necessary. Serve hot, garnished with your favorite dairy-free toppings.