Preheat the oven to 425 degrees F. Line a baking sheet with parchment paper or foil.
Place the sweet potatoes on baking sheet, and prick each one a couple of times with a fork. Bake until very tender, about 45 minutes.
In a medium mixing bowl, combine the rice, black beans, cumin, garlic powder, and salt. Set aside.
Make the rustic salsa: In a medium bowl, combine the bell pepper, cherry tomatoes, red onion, lime juice, cilantro and olive oil. Season the mixture with salt and pepper, and toss to combine. Set aside.
Make the guacamole: Peel the avocado and extract the pit. Place the avocado flesh in a medium bowl and mash with a fork. Once you’ve broken it up a bit, add the garlic, lime juice, cilantro and salt. Mash the avocado until the seasoning is evenly distributed and you have a chunky paste. Set aside.
Place each baked sweet potato in a shallow bowl. Cut along the top of the sweet potato and pull back the skin. Spilt the sweet potatoes a little bit to make room for the fillings.
Divide the rice and bean mixture among the sweet potatoes (spillover is fine!). Top each bowl with ¼th of the rustic salsa. Finish each plate with a dollop of the guacamole and some shredded cabbage on top. Serve with hot sauce on the side if you wish.