Wash, stem and seed the banana peppers. cut into thick rings 2 to 3 cm (1 inch) wide. Add to bowl.
Wash, stem and seed the sweet peppers. Cut into chunks. Add to bowl.
Wash the cauliflower. Cut off leaves and stalk. Cut into small florets; wash again. Drain well, add to bowl.
Set bowl aside.
Get a large pot and put on the stove top. Add the coriander seed, and toast it for a few minutes until it just starts to darken and release a bit of scent.
Add everything from the water down to and including the mustard seed. Stir well, then bring to a boil, then lower to a simmer and let simmer for 3 minutes.
Turn heat off.
Pack veg into the jars you are using to within 3 cm (1 inch) of the top of the jar. That will tell you how many jars you are using.
In each 1 litre (US quart) jar put 2 bay leaves, 2 cloves, 2 cloves garlic, and ¼ teaspoon pickle crisp (optional.) (Half that for the half-litre / US pint jars.)
Using a ladle, divvy the pickling solution out amongst the jars to within 2 cm (½ inch) headspace.
If you are short of solution, zap some additional cider vinegar in microwave for 2 minutes to heat it, then use that to top up.
Don't worry about all the seed ending up on top; as you debubble, they will get pushed down.