Chop the onion, garlic, bell pepper, and green onions if using. Drain and rinse the black beans.
Heat the extra-virgin olive oil in a skillet. Add the onion, garlic, and bell pepper. Cook until the onion is soft (about 4-5 minutes).
Stir in the smoked paprika, cumin, cayenne pepper, and dried oregano. Cook for about a minute.
Add the frozen cauliflower rice. Cook until heated through, for about 5 minutes.
If using raw cauliflower, grate it using a box grater or pulse it in a food processor until it resembles rice grains. Add a couple of minutes to the cooking time, until the "rice" is tender but not mushy.
Mix in the black beans and diced tomatoes. Warm everything for a couple of minutes. Season with salt and pepper.
Remove from the heat. Garnish with parsley, cilantro, and optional green onions. Enjoy!