Mary Berry's Christmas chutney

INGREDIENTS

• 900g tomatoes
• 3 red peppers, 1 large aubergine and 1 green pepper (total weight of about 900g/2lb)
• 700g onions , peeled and fairly finely chopped, by hand or in a food processor
• 4 fat cloves garlic , crushed
• 350g granulated sugar
• 300ml/½pint white wine vinegar or distilled malt vinegar
• 1 tbsp salt
• 1 tbsp coriander seeds, crushed
• 1 tbsp paprika
• 2 tsp cayenne pepper