Sage, potato and pancetta galette

Instructions

1. To make the flaky rye pastry, mix the flours and salt together in a large bowl. Rub the butter into the flour using your fingertips or a pastry cutter until the mixture is pebbly. You want to rub the butter into flatter pieces rather than into something that resembles breadcrumbs (this will result in a flakier and shorter pastry). Drizzle in the vinegar and sprinkle over enough iced water to just bring the dough together. It will still be shaggy and should just hold together when pressed. If there are still dry or floury spots, sprinkle over the remaining water, a teaspoon at a time, until the dough just comes together. Flatten into a disc, wrap in plastic wrap and chill in the fridge for at least 1 hour.
2. Preheat the oven to 190°C. Line a 25 cm round baking tray with baking paper.
3. Remove the dough from the fridge and let it sit at room temperature for 10 minutes to make it easier to roll. Roll the dough out on a lightly floured work surface into a large circle, 3–4 mm thick, massaging the edges as you roll to prevent it from cracking too much. Drape the pastry over the prepared tray.
4. In a small bowl, combine the crème fraîche, comte and lemon zest. It will be a thick paste. Season well then spread over the base of the pastry, leaving a 4–5 cm border.
5. Place the potato slices and sage in a bowl and drizzle with the olive oil. Season well, then layer onto the cheese mixture, tucking the pancetta in as you go. You want some of the pancetta to be peeking through the potato. Fold the pastry border over the outer edge of the filling to form a galette. Whisk the egg with 1 teaspoon of water and brush the egg wash over the pastry. Drizzle a little extra olive oil onto the potato and bake for 40–45 minutes, until the pastry is golden and the potato is cooked through. Allow to cool for 10 minutes, then serve.