Step 1

Preheat the oven to 400°F.

Step 2

Place the cauliflower and cabbage on a large sheet pan. Drizzle with the olive oil and sprinkle with the cumin, coriander, and salt. Use your hands to mix everything together and spread it out into an even layer. Roast, stirring every 15 minutes, until the vegetables are softened and browned in spots, about 45 minutes. (I roasted my cabbage and cauliflower on two separate sheet pans. I cooked the cauliflower for 25 minutes and the cabbage for 10 minutes. Both ways work!)

Step 3

Evenly divide the Avocado Sauce and roasted vegetables among the tortillas. Serve immediately with the radishes, serranos, avocado slices, and cilantro, if using.