Given the cook-at-home nature of Spinneys and natural variations in ingredients, nutritional information is approximated."

Savoury caramelised onion galette

French 40 Mins Prep · 45 Mins Cook

To make the pastry, combine the flour, 2 tbsp Parmesan and salt in the bowl of a stand mixer fitted with the paddle attachment.
Mix in the cold, cubed butter with the machine running on a low speed until small pieces of butter are visible and the mixture as a whole just begins to take on a pale yellow colour (indicating that the butter has been worked in sufficiently).
Stir the water and lemon juice together and add this to the dough all at once, mixing until the dough just comes together.
Shape the dough into a disc, wrap and chill for at least 2 hours before rolling.
Roll the pastry out on a lightly floured surface to 5mm thick. Sprinkle the remaining 2 tbsp Parmesan in the middle.
Transfer the disc to a large lined baking sheet.
Preheat the oven to 180°C, gas mark 4.
Peel the onions, leaving the roots intact.
To make the filling, cut the onions into 8 wedges each (the roots should keep the wedges together).
Place the onion wedges in a bowl and gently toss in the sugar and cider vinegar.
Arrange the onion wedges, cut side up, in the middle of the rolled out pastry disc.
Fold the edges of the pastry up over the onions so it overlaps slightly.
Brush the edges with the whisked egg and bake in the preheated oven for 30-45 minutes or until the pastry is golden and the onions are roasted and sticky.
TOP TIPThe pastry can be frozen for up to 3 months and thawed in the fridge before rolling.