Roasted cauliflower shawarma with pomegranate and tahini

Ingredients

• 1 whole cauliflower
• 4 tbsp tahini sauce
• 1 tbsp pomegranate molasses
• 1 1/2 tbsp pine nuts, toasted
• 1 small green chilli, finely chopped
• 2 tbsp pomegranate seeds
• 1 tsp dried rose petals
• 1 tbsp roughly chopped flat-leaf parsley
• 1 glug extra virgin olive oil (optional)
• 40 g unsalted butter, softened to room temperature
• 1 lemon (juice only)
• 1 garlic clove, minced
• 1 1/2 tbsp finely chopped coriander
• 1 tbsp ground cinnamon
• 1 tbsp ground sumac
• 1 1/2 tsp ground cumin
• 1/2 tsp ground allspice
• 1 pinch ground nutmeg
• 1 pinch ground cardamom
• 1 tbsp lemon juice (optional)
• 1 garlic clove, minced (optional)
• 100 ml iced water
• 100 g tahini paste