Preheat the oven to 200°C (390°F).
Add the chicken, spices, and half of the olive oil to a bowl. Mix to combine.
Place a large oven-safe pan over medium-high heat. Add the remaining olive oil and, once hot, sear the chicken for 3–4 minutes on each side, until golden. Transfer to the oven and cook for 14–15 minutes, or until the internal temperature reaches 74°C (165°F). Remove and rest for 5 minutes before slicing.
In a saucepan, heat the black beans over medium heat. Add the ground cumin, chilli powder, and seasoning to taste. Stir well and simmer for 5–7 minutes. Add the coriander and set aside.
Add all of the corn salsa ingredients to a bowl and mix to combine.
Cut and chop the cauliflower into bite-sized pieces, including the core. Add to a blender and process into rice-sized pieces, working in batches to avoid it turning to mush.
Place a pan over medium-high heat. Add the olive oil and cauliflower and sauté for 5–6 minutes, until any water has evaporated and the cauliflower starts to take on colour. Season to taste and set aside.
Serve all elements into 5 x 750ml meal prep containers. Garnish with spring onion, sour cream, and sriracha mayonnaise, if using.