Christmas Dinner Sausage Rolls

Pastry

• 300 g plain flour
• 150 g unsalted butter, diced (1 cm), then frozen
• 100 g water, cold
• 1 tsp fine sea salt

Filling

• 12 - 15 fresh sage leaves, to taste
• 80 g cooked, peeled chestnuts
• 20 g olive oil
• 200 g onions, cut in wedges
• 400 g turkey mince, broken in pieces
• 1 pinch ground black pepper
• plain flour, for dusting
• 6 slices streaky bacon
• 340 g chipolata sausages
• 1 medium egg, beaten, for glazing