1. Place the flour and 100g butter into a large bowl and using your fingertips rub until it looks like fine breadcrumbs.. Using a wooden spoon, slowly mix in the water, until the dough becomes pliable. The amount of water required may vary slightly according to the absorbency of the flour. Place the dough on a floured surface and knead well until it feels elastic. Wrap in cling film and leave in the fridge for 1 hour.
2. To make the filling, mix the thyme and sausage meat and season.
3. Return the chilled dough to the floured work surface and roll into a rectangular shape measuring 60 x 30cm.
4. Flatten the butter into a rectangle about 1cm thick and lay it over two-thirds of the dough. Fold the remaining one-third of the dough over the buttered dough. You will be left with one third of buttered dough. Fold this over so that the dough is in 3 layers. Return the dough to the fridge to chill for a further hour.
5. Scatter some more flour over the work surface and roll out the dough to the same sized rectangle as before. Repeat the folding process, one side on top of the other, and place the dough back in the fridge for another hour.
6. Repeat this process another 2 times before wrapping the dough in cling film and leaving it to rest over night in the fridge.
7. Roll the dough out to approximately 5mm thick. Then cut 13cm rectangles from the dough (the dough may be frozen at this stage if not all of it is used).
8. Cut into long 10cm strips fill with sausage meat filling brush the edges and seal, place onto a baking tray and leave to double in size. Egg wash then bake at 200°C for 15 minutes until golden brown.
9. To make the sauce put the raisins and HP sauce into a food processor and blitz until smooth, serve with the sausage rolls.