Tomato Ketchup from What to Eat Now (Spring & Summer) by Valentine Warner

Ingredients

• 1 tablespoon flaked sea salt
• 1 teaspoon English mustard powder
• 150 ml malt vinegar
• 200 g light brown muscovado sugar
• 4 garlic cloves
• 250 ml cider vinegar
• 4 kg ripe tomatoes
• 2 medium onions
• 1 heaped teaspoon celery salt
• 1 teaspoon ground white pepper
• ½ teaspoon ground ginger
• 1 cinnamon stick
• 1 heaped teaspoon ground cloves
• 1 teaspoon ground allspice