Regal Smoked Salmon Bruschetta with a Currant and Red Onion Pickle

Pickle
1/3 cup apple cider vinegar
1 tablespoon water
1 tablespoon caster sugar
1 teaspoon sea salt
pinch chilli flakes
1 tablespoon wholegrain mustard
1 clove garlic, crushed
1 small red onion, very thinly sliced
2 tablespoons currants
2 tablespoons capers
To serve
100-gram pack Regal Manuka Smoked Salmon Slices
4 slices sourdough bread, grilled and rubbed with a cut clove of garlic
mayonnaise
½ small telegraph cucumber, halved, seeded and thinly sliced on the diagonal
fresh herbs, use either mint, dill, basil or parsley
olive oil, sea salt and ground pepper