Preheat the oven to 425 F.
Remove the thick stem and leaves from the head of cauliflower and chop it into florets. Prepare a baking tray with parchment paper (optional) and add the cauliflower to the tray. Drizzle with the oil and sprinkle with all the spices. Use your hands to mix until all the florets are coated
Roast the cauliflower in the oven for 30-40 minutes until tender and browned.
While the cauliflower is cooking, start cooking your rice according to the package instructions. This will vary depending on the type of rice you use.
While the rice and cauliflower are cooking, prepare the bowl ingredients. Dice the red onion, get the salsa and lime ready, drain and rinse the black beans and prepare the avocado.
Once the rice is ready, divide it between 4 bowls or containers.
Divide the the cauliflower, onion, black beans, corn and cilantro between each serving.
Finish each bowl with salsa and avocado (suggested to leave avocado off until serving if making for meal prep) and serve with a wedge of fresh lime.