BBQ pulled pork sandwich

INGREDIENTS

• 2 onions , sliced
• 3 bay leaves
• 1 tbsp each mustard powder and smoked paprika
• 1.5-2kg/3lb 5oz-4lb 8oz) pork shoulder , boned with rind attached and tied (ask your butcher to do this)
• 140g tomato ketchup
• 4 tbsp red wine vinegar
• 1 tbsp Worcestershire sauce
• 3 tbsp soft dark brown sugar
• 2 French stick , sliced into rolls, and coleslaw, to serve