In a small bowl or a blender/food processor, combine the sour cream (or Greek yogurt), fresh cilantro, lime juice, minced garlic, salt, and optional sugar. Blend or whisk until smooth and creamy. If the crema is too thick, add water or milk one tablespoon at a time until you reach your desired drizzling consistency. Taste and adjust seasoning as needed. Set aside.

Preheat your oven to 400°F (200°C) or set your air fryer to 375°F (190°C).

In a large mixing bowl, toss the cauliflower florets with olive oil, chili powder, ground cumin, smoked paprika, garlic powder, salt, and black pepper. Ensure all florets are evenly coated.

If roasting in the oven: Spread the seasoned cauliflower in a single layer on a large baking sheet. Roast for 20-25 minutes, flipping the cauliflower halfway through, until it's tender, slightly caramelized, and has a nice char on the edges.

If air frying: Place the seasoned cauliflower in the air fryer basket in a single layer. You may need to cook in two batches to avoid overcrowding. Air fry for 15-20 minutes, shaking the basket every 5 minutes, until the cauliflower is tender and crispy.

While the cauliflower is cooking, warm your tortillas. You can do this in a dry skillet over medium heat for about 30 seconds per side until pliable and slightly charred, in the microwave wrapped in a damp paper towel, or wrapped in foil in the oven for a few minutes.

To assemble, place a generous spoonful of the roasted cauliflower into each warm tortilla. Drizzle liberally with the prepared cilantro lime crema.

Add your desired toppings such as diced avocado, thinly sliced red cabbage, pickled red onions, or crumbled cotija cheese. Serve immediately with extra lime wedges on the side.