To begin, rinse and prepare all the vegetables. Slice each spring onion into 3 shoots equal in length. Slice the celery into pieces no more than 1cm thick

Peel the carrots and slice them to thin rounds about 3mm thick, using a mandoline vegetable slicer if possible. Do the same for the unpeeled cucumber

Slice open the peppers, remove the stem, seeds and pith, and slice into medium-thin strips. Remove the thick stalk from cauliflower and cut away the flesh, preserving the small florettes

Fill a large, deep pan with water. Place four 1-quart jars and their lids inside and bring to a full simmer/low boil for 15 minutes

Bring the water and vinegar to a boil in another large pan. Add the sugar, salt, pepper, and bay leaves. When some of the water has evaporated, add the sliced carrots and cauliflower tips and boil for 2 minutes

Next, add the onion, celery, and peppers and cook for another 2–3 minutes. Lastly, add the cucumber and boil for 4–5 minutes (no more than 5). Lift the vegetables from the liquid using a slotted spoon and transfer to a bowl. Retain the cooking liquid

Remove the jars from the pan using tongs and set on a clean tea towel or rack. When the vegetables are cool, begin transferring the mixture to the jars without packing them in too snugly (a small soup ladle works well for this step). Filter the warm cooking liquid and pour it over the vegetables, leaving about 2.5cm from the top of the jar. Close well but not too tightly

Return the jars to the large deep pan and add water to 2.5cm above the tops of the jars. Bring to the boil for 30 minutes

Remove the jars from the water with tongs and set aside to cool. When the jars are completely cooled, test the seal and firmly tighten the lid. Conserve the jars for at least a month before opening. The pickle can be stored for up to 3 months in a cool, dry place away from light. Consume within 3 days of opening a jar