Preheat oven to 400 F.

Place the whole head of cauliflower in a pot of boiling water for 7 minutes. Remove and pat dry. Place the cauliflower head and all other selected vegetables on a parchment-lined sheet pan, drizzle with roughly 5 tablespoons olive oil, and season with salt and pepper. Roast for 45 minutes or until browned.

While the vegetables are roasting, make the lemony tahini sauce: Whisk together in a bowl until smooth the tahini, ice water, lemon juice, olive oil, salt and pepper to taste.

To assemble: Place the vegetables on a platter with the whole cauliflower as the centerpiece and drizzle with the tahini sauce. Garnish with wedges of pomegranate for extra color if desired.