Easy Cauliflower Tacos

Preheat oven to 450°F. Line a large rimmed baking sheet with parchment paper.

Toss cauliflower, onion, oil, chili powder, salt and pepper together in a large bowl until well combined. Spread in an even layer on the prepared baking sheet. Roast until deeply brown in spots and tender, 25 to 30 minutes. Transfer to a bowl; add lime juice and toss to coat.

Divide the cauliflower-onion mixture evenly among tortillas (about 1/2 cup per tortilla). Top each with 2 avocado wedges. Top with radish slices and cilantro, if desired.