Makes 8 large or 16-20 bite-sized sausage rolls
500g chestnut mushrooms, cleaned and finely chopped
½ tsp each thyme and sage, finely chopped
1 medium onion, diced
1 small egg, beaten
500g packet of all-butter puff pastry
Polenta for dusting
Preheat the oven to 180ºC/350ºF/gas 4.
First, make your filling by gently frying off your onions in the butter until translucent. Add the mushrooms. They will lose lots of moisture initially, cook this off until you have a drier mix. Decant to a mixing bowl and cool slightly.
Into the bowl toss in your remaining ingredients (except the pastry and polenta!) and stir thoroughly. The mixture should be a pâté texture.
Roll out your puff pastry into a big rectangle, about the thickness of a pound coin. Split into two, and then cut into further rectangles/squares, about the size you want your sausage rolls to be. We made 6 medium sized sausage rolls, so cut the pastry into 12 pieces.
Divide your sausage mixture into the same number of sausage rolls you plan to make. Mould into sausage shapes and place on top of half of the pastry pieces. Brush the sides with egg wash, then top with a second piece of pastry. Crimp the edges together with a fork along two sides, snip some air holes on top with a pair of scissors, and egg wash the top of the sausage roll.
Line your baking tray with parchment and sprinkle over polenta. The polenta absorbs the fat and moisture while the pastry cooks, ensuring the sausage rolls have a crisp base. Place the complete sausage rolls on the tray as you make them.
Bake for about 20-25 minutes until golden. Cool slightly on a wire tray before serving. Delicious with piccalilli or English mustard.