Cut your cauliflower into bite-sized florets. In a bowl, toss the florets with a drizzle of neutral vegetable oil, salt, and spices, until cauliflower is evenly coated.
On a baking sheet lined with parchment paper, roasted cauliflower in the oven for about 25 minutes, or until tender but slightly browned.
While the cauliflower is cooking, make the pico. First, cut the jalapeño in half and remove the ribs and seeds. Then, dice the jalapeño, tomatoes, and red onion.
Mix all of the pico ingredients in a bowl and let rest for at LEAST 10 minutes. Taste, and adjust seasonings if necessary.
When cauliflower is done, remove from the oven and let cool slightly.
Now, build your tacos - add on the cauliflower, spinach, pico, and any other toppings you'd like. (Guacamole or sour cream would be delicious!)
Serve, and enjoy!
Notes
If you don't have chipotle chili powder for the cauliflower, sub with regular chili powder.