Pickled green beans - Good Food Middle East

Ingredients

• 1kg green beans
• 140g coarse crystal sea salt
• 1 tbsp black peppercorns
• 1 tbsp coriander seeds
• 1 tbsp yellow mustard seeds
• 10 cloves
• few pieces of mace blades
• pinch of dried chilli flakes (optional)
• 2 bay leaves
• 700ml white wine vinegar, plus 3½ tbsp
• 100g white sugar
• 1 finely chopped red onion