For the pastry
- 350g plain flour
- 1 tsp caster sugar
- 220g unsalted butter, cold
- 100g ice water
For the filling
- 50g unsalted butter, softened
- 200g soft brown or light muscovado sugar
- 3 eggs
- 100g golden syrup
- 50g black treacle
- 1tsp vanilla
- 1tbsp dark rum
- 150g pecan pieces and 80g pecan halves
- 25g salted butter, melted
- 4tbsp caster sugar
- Line a 20 x 30cm Swiss roll tin with baking paper and heat the oven to 190°C/170°C fan/mark 5.
- In a food processor, add all of the pastry ingredients except the water and whizz until the mixture resembles a coarse meal.
- Strain the ice water just before using, then, with the motor on, drizzle it in just until everything comes together. Pulse a couple of times more, then tip out onto your work surface. Using the palm of your hand, gently pat the dough into a square. Fold in half and press together again. Rest the dough for 30 minutes in the fridge while you get the filling ingredients together.
- In the bowl of an electric mixer, cream together the butter and soft brown sugar until light and fluffy. Add the eggs one by one and then the golden syrup, black treacle, vanilla and rum. Finally mix in 150g pecan pieces (reserving the pecan halves for the topping) and set aside.
- On a lightly floured surface, roll out the pastry to about 24 x 34cm. Fold the dough loosely in half and then in half again, but do not press down. Gently lift the folded dough onto the prepared tin, placing it in one corner, then unfold it so it lays over the tin with a bit of an overhang. Pour in the filling mixture (making sure that it comes right up to the edges) and then fold the edges back over the filling in a loose, rustic way.
- Brush the pastry with the melted butter and sprinkle with the caster sugar. Bake for 40–45 minutes, or until the pastry is golden and the filling is set.
- If you have a kitchen blowtorch, you can use it to finish the edges of the pastry by caramelising the sugar, which will create a golden, crisp sugar crust.