Preheat the oven to 200°C.
Pulse the flour, butter, two eggs, and water in a food processor until a dough forms.
Roll out the dough to 0.5cm thick and cut into two circles to fit the dishes.
Place dough discs on a baking sheet, brush with egg, and bake for 8 to 10 minutes.
Fry the onion in oil until soft, then add garlic for one minute.
Add venison and cook until browned on all sides.
Simmer wine and vinegar until reduced by half, then stir in seasoning and grated chocolate.
Divide filling between two ovenproof dishes and top each with a pastry disc.
Bake for 10 minutes until the pastry is golden and the filling is cooked.
Garnish with rosemary to serve.