Preheat oven to 375 degrees. Add sweet potato to a large bowl along with 1 1/2 tablespoons olive olive, 1/2 teaspoon salt and cumin. Toss to combine everything together. Spread on a baking sheet and roast until soft, about 15-20 minutes.
While the sweet potato cooks, add the garlic powder, paprika, oregano, onion powder, and 3/4 teaspoon salt to a small bowl. Add chicken to the same bowl you tossed the sweet potato in, toss with spice mix until evenly coated.
Heat a large cast iron skillet to a medium heat. Add 2 teaspoons of olive oil. Once the pan is hot, add chicken. Cook until blackened and cooked through, about 3-4 minutes on one side and 2-3 minutes on the other. Remove from the pan.
Add remaining olive oil the pan along with onion, Brussels sprouts and garlic. Sauté until onion, Brussels and garlic and all softened, about 5 minutes. Add black beans, cook another 1-2 minutes. Season with a little bit of salt and pepper. Remove from heat until sweet potatoes are cooked.
Cook rice according to package directions. Toss with chopped cilantro and season with salt and pepper.
To assemble. Put rice in the bottom of 4 bowls. Top with onion Brussels sprout mixture, sweet potatoes and chicken. Drizzle with avocado cream (I like to put the cream in a small ziplock bag and cut the tip off to drizzle easily) and sprinkle with cilantro.