Preheat your oven to 400°F (200°C).

Cut the cauliflower into bite-sized florets and place them in a large mixing bowl. Drizzle with olive oil, and sprinkle salt and pepper. Toss until evenly coated.

Spread the seasoned cauliflower florets in a single layer on the prepared baking sheet. Roast for 20–25 minutes, flipping halfway through.

Wash and dry your mixed greens. Thinly slice the red onion.

In a small bowl, whisk together tahini, lemon juice, salt, and pepper. If using, add minced garlic. Gradually stir in water until smooth.

Once the cauliflower is roasted, let it cool for a few minutes. Combine the roasted cauliflower, mixed greens, red onion, and pumpkin seeds in a large mixing bowl.

Drizzle the tahini dressing over the salad mixture and toss gently.

If using, add crumbled feta cheese. Serve immediately or refrigerate any leftovers.