Preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper or a silicone baking mat for easy cleanup.
Prepare the cauliflower by cutting it into bite-sized florets. Place in a mixing bowl.
Season the cauliflower: Drizzle the cauliflower with olive oil and sprinkle taco seasoning over it. Toss well to ensure the cauliflower is evenly coated.
Roast the cauliflower: Spread the seasoned cauliflower in a single layer on the prepared baking sheet. Roast in the oven for 25-30 minutes, flipping halfway through, until crispy and golden.
Warm the tortillas: While the cauliflower is roasting, warm your tortillas in a dry skillet over medium heat for about 30 seconds on each side or wrap them in a damp towel and microwave for 20-30 seconds.
Assemble the tacos: Once the cauliflower is roasted, warm, and ready, place a generous amount of cauliflower into each tortilla. Top with shredded lettuce, avocado slices, salsa, and fresh cilantro. Squeeze lime wedges over the top for extra zest.
Serve and enjoy: Serve the tacos immediately with optional toppings such as vegan sour cream, pickled red onions, or shredded cabbage. Enjoy with a side of rice or beans for a complete meal.