Bring vinegar essence, 650 ml water, sugar and salt to the boil and allow to reduce slightly. Clean and wash the zucchinis and cut them into slices with a waiter knife. Wash the thyme and pluck the leaves from the stems. Fill the zucchinis, thyme and mustard seeds into the prepared glasses up to about 2 cm below the edge. Cover with boiling hot stock. Close the glasses well. Leave to infuse for at least 2-3 days
Shelf life approx. 4 months