Ingredients 4 portions – 1hour prep time and 40 minutes cooking
500g button mushrooms , stalks removed and finely chopped
1 sprig thyme, leaves stripped off
600g Pork fillet
1 tbsp. English mustard
500g pack all-butter puff pastry
3 slices Parma ham
1 egg yolk , beaten
50g plain flour
1 tbsp. chopped mixed herbs , such as chervil, chives and tarragon
½ tbsp. melted butter
To make the crêpes, whizz the flour, egg and milk with a pinch of salt in a blender or processor until smooth. Pour into a jug and stir in the herbs and some seasoning. Leave to rest.
Fry the mushrooms in a little oil until they give up all their moisture and it has evaporated, leaving you with a thick paste. Add the thyme leaves and some seasoning and keep cooking for a few minutes. Cool.
Stir the melted butter into the crêpe batter, heat a 15cm crêpe pan and oil it lightly. Pour in enough batter to make a thin layer on the base of the pan, cook until the top surface sets and then turn over and cook briefly. Remove and repeat with the rest of the batter. This will make a couple more than you need so choose the thinnest ones for the recipe.
Sear the pork all over in a little oil in a very hot pan. Brush with the mustard, season and allow to cool.
Lay a large sheet of cling film on a kitchen surface and put two crêpes down on it, overlapping a little. Lay over the Parma ham. Spread the mushroom mixture over the ham and put the beef in the centre. Roll the cling film up, taking the crêpe with it, to wrap the pork completely into a nice neat log. Chill for 1 hour.
Heat the oven to 200C/fan 180C/gas 4. Roll out the pastry, remove the cling film and wrap the pork in the pastry like a parcel, with the ends tucked under. Trim to keep it nice and neat. Brush with egg, score with shallow lines across the top and chill for 20 minutes.
Cook for 40 minutes. The best way to test if the meat is done to your liking is to neatly and carefully stick a skewer into the pork, count to three and then test it against your inner wrist. If it is cold the beef will be raw, if it is warm then the beef will be rare and if it's hot, it'll be cooked through. Leave to rest for 10 minutes before carving.