For the pickling liquid, in a pan bring all of the pickling liquid ingredients to the boil and leave to simmer on a low heat.
Sterilise both a 1 litre/1¾ pint pickling jar with a screw top lid and the lid in a large pot of boiling water that boils for at least 10 minutes. (Or use several smaller jars with lids.) Lift the jars out of their water bath with a pair of jar tongs. Empty the water.
Alternatively they can be sterilised in a dishwasher.
For the pickle, quickly fill the jars with the tomatoes, herbs and spices.
Using a jug or a funnel pour the hot pickling liquid into the jar, pour it all the way to the top and seal, ensuring as little air as possible remains in the jar.
The pickle will keep for up to a year.
Keep refrigerated once opened and finish within two weeks.