Preheat the oven to 425°F (220°C).

In a mixing bowl, toss the cauliflower florets with olive oil, salt, pepper, and garlic powder until evenly coated.

Spread the cauliflower on a baking sheet in a single layer.

Roast in the preheated oven for 25-30 minutes, or until golden brown and tender, stirring halfway through.

In a large bowl, combine the roasted cauliflower, cherry tomatoes, cucumber, spinach, feta cheese, and avocado.

In a small bowl, whisk together the lemon juice, tahini, minced garlic, water, and salt until smooth.

Drizzle the dressing over the bowl and toss gently to combine.

Serve immediately and enjoy!