Tarte tatin

Pastry

• 100 g unsalted butter, cut into pieces, plus extra to grease
• 200 g plain flour, plus extra to dust
• 50 g cold water
• 1 pinch sea salt

Caramel and filling

• 150 g caster sugar
• 70 g unsalted butter, cold, cut into pieces
• 1030 g water
• 1 tsp freshly squeezed lemon juice
• 8 Granny Smith apples, peeled and cut into sixths (see Tips)
• 1 tbsp vinegar