Cut off the florets from the cauliflower head. Chop into same size chunks. Pulse the cauliflower in the food processor about 15 times - about the size of rice. This will take 2-3 batches.
In a large skillet, heat the oil over medium high heat.
Add onion and pepper. Cook about 5 minutes or onion is translucent.
Add the garlic and spices. Cook thirty seconds.
Add the cauliflower rice and salsa. Put the lid on the skillet. Reduce heat to medium. Cook 7-8 minutes.
Remove from heat and salt and pepper to taste. Add tomatoes and cilantro. Serve warm.
Alternatively, you could mix everything together into a baking dish and bake for 40 minutes at 350 degrees - being sure to stir halfway through.
Recipe by Whisk Together at https://www.whisktogether.com/2015/08/13/mexican-cauliflower-rice/