1. In a large bowl whisk together the milk, cream, eggs, salt and sugar. Slowly whisk in the flour until very smooth. (This can be done in a large food processor or blender in two batches if preferred.)
2. Heat a 20cm - 24cm crepe pan or frying pan on a medium to high heat. Pour a small amount of vegetable oil on the pan and work into the surface with a kitchen towel. Use the retained batter to practise and help season the pan. Take about 70-80ml batter and pour onto one side of the pan, immediately swirl the batter around and down to cover the whole pan, pouring off the excess into a bowl (the excess can be added to the batter and used again.) When the crepe is covered with small holes and browned on one side, carefully turn the crepe over with a spatula and cook on the other side until browned. Place the cooked crepe on greaseproof paper over a cooling rack. Interleave each crepe with greaseproof paper to make a stack. Continue until all the batter is used. You should have at least 12 good crepes (any crepes that are not used can be wrapped in paper and kept in the fridge for heating up later).
3. Preheat the oven to 200C Gas 6.
4. To make the turnovers, peel and core the apples cutting them into quarters and then slicing into chunks. Place one quarter of the apples in a pan with 160ml apple juice and 160ml water. Heat the pan and simmer the apples for 5 minutes, then add the remaining apples and cinnamon and a pinch of salt and cook for about 3 minutes. The filling should be partly puree (from the apples that were cooked first) but also retain apple chunks that are tender but firm. Add 100ml of Sticky Toffee Sauce. Stir gently and cook for a further minute and then take off the heat.
5. To prepare the crepes, melt the butter. Using a broad pastry brush apply butter on the more attractive brown side. Then turn the crepe over and put about 60ml of filling in the centre of the crepe. Fold two sides over the filling, then fold the bottom over the mound of filling, and roll the turnover over the top part of the crepe to form a cylindrically-shaped turnover. Place on a backing tray with the fold on the bottom.
6. Put the turnovers in the hot oven and cook for approximately 8 minutes, watching carefully to ensure they do not burn. Remove from the oven. Serve with cream or ice cream and more Sticky Toffee Sauce if you like.