Arrange cauliflower on a large rimmed baking sheet. Drizzle with olive oil and sprinkle with taco seasoning. Toss to combine and arrange cauliflower in a single layer.
Bake for 15 minutes. Remove from oven and flip florets over. Continue to bake, 15–20 minutes longer, until browned and crisp. (This is a good time to add your tortillas to the oven, bake wrapped in foil for 15 minutes.)
Meanwhile, make the lime crema. Place all of the ingredients in a blender or food processor and blend until smooth.
Enjoy the roasted cauliflower in tortillas with your favorite toppings.