1 small Bramley apple, peeled, cored and diced
125g caster sugar
Butter, for greasing
300g self-raising flour, plus extra for dusting
150g shredded suet
Finely grated zest of 1 lemon
200ml whole milk, plus extra to brush
1. In a small pan, gently heat the blackberries, apple and 75g of the sugar until the fruit softens. Bring to the boil and cook for 10 minutes until jammy. Pour into a bowl and leave to cool.
2. Butter a big piece of baking paper and place it, butter-side up, over a big piece of foil. In a bowl, mix the flour, remaining sugar, suet and lemon zest with a pinch of salt, then gradually add enough milk so the mix forms a dough (you may not need all the milk). Bring together and briefly knead, then shape into a ball.
3. Roll out the dough on a lightly floured surface to a 20cm x 30cm rectangle, trimming the edges with a sharp knife. Spread with the blackberry mixture, leaving a 2cm border. Brush the edge with milk, then roll up from the short end.
4. Place in the centre of the buttered paper with the pastry seam on the bottom, fold the paper and foil over and seal, making a pleat in the foil and paper to leave room for the pastry to puff up and rise. Ensure the ends are well sealed.
5. Loosely scrunch up a few large pieces of foil and use to make a rack in the slow cooker. Put the roly poly on top, then pour boiling water around the edge to just cover the foil rack. Cover with the lid and cook on high for 2-3 hours until firm to the touch. Rest for a few minutes, then serve with good-quality custard or ice cream.
- To oven-cook, preheat to 200ºC/fan180ºC/gas 6. Put the foil-wrapped pudding on a trivet in a deep roasting tin. Pour in boiling water to just below the level of the roly poly. Cover the tin tightly with foil and bake for 40 minutes.
- Serve with a chilled, dessert French Muscat, such as Muscat de Beaumes de Venise.