1kg/2lb 4oz small pickling onions or shallots
4 strips pared orange peel (strips of orange peel with no pith)
2 sprigs rosemary or thyme
125ml/4fl oz balsamic vinegar
100g/3½oz demerara sugar
1–2 tsp fennel seeds
1 tbsp olive oil
1 tsp pink peppercorns
2 tsp sea salt
125ml/4fl oz white wine vinegar