Preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper for easy cleanup.
In a large bowl, combine the olive oil, chili powder, cumin, garlic powder, onion powder, smoked paprika, salt, and pepper. Mix well to create a marinade.
Add the cauliflower florets to the bowl and toss until they are evenly coated with the marinade.
Spread the cauliflower in a single layer on the prepared baking sheet.
Roast in the preheated oven for 25-30 minutes, or until the cauliflower is tender and golden brown, stirring halfway through for even cooking.
Once roasted, remove from the oven and drizzle with lime juice. Toss gently to combine.
Serve warm, garnished with fresh cilantro and diced avocado.