Preheat your oven to 425°F (220°C). Toss cauliflower florets with olive oil, cumin, paprika, chili powder, salt, and pepper in a large bowl. Spread on a baking sheet and roast for 20–25 minutes until golden and crispy, flipping halfway.
While the cauliflower roasts, blend sour cream or Greek yogurt, cilantro, lime juice, olive oil, salt, and pepper until smooth. Taste and adjust lime or salt as needed. This sauce adds a zesty, creamy finish to the tacos.
Warm tortillas in a skillet until slightly charred. Fill each with roasted cauliflower, drizzle with crema, and add toppings like avocado, pickled onions, or cheese. Serve immediately for the best texture.