Remove any strings from the runner beans then chop the beans into small pieces.
Put into a large pan, cover with boiling water and a teaspoon of salt.
Bring to the boil and cook for 10 minutes until tender.
Peel core and roughly chop apples.
Peel and finely chop the onion.
Core and finely chop the red pepper.
Drain runner beans then return them to the pan.
Add onions, apple, and pepper to the pan.
Pour in the vinegar and simmer the fruit and vegetables until nearly soft.
Add the canned tomatoes and chilli paste to the pan.
Put in the salt, sugar, and fish sauce, if using.
Simmer, stirring frequently, until the chutney is thick.
Pot into warm sterilised jars and seal immediately.