Gather and weigh your ingredients
Line a terrine mould with clingfilm in both directions, allowing a 5 cm [2"] overhang on each side and set aside
Place the bacon between 2 pieces of clingfilm, and using a rolling pin, roll the streaky bacon to thin out
Line the Terrine Mould [horizontally, on top of the clingfilm] with the bacon, slightly overlapping each slice, reserving 3 slices for the top
Slice the chicken breast into 3 pieces lengthways - 9 strips in total
Cut each boneless chicken leg into 4 pieces
Slice all the mushrooms and saute in a hot pan until cooked. Season with salt and white pepper and set aside to cool.
Pre-heat oven to 160c
Fill a medium saucepan with 3/4 water and 1 tsp salt and bring to the boil.
Place the cut chicken legs and 4 strips of chicken breast into the boiling water and poach for 6-7 minutes or until the internal temperature is 75c. Remove from the water and allow to cool [Note 1]
Place the other 5 uncooked strips of chicken breast into a food processor along with a pinch of salt and white pepper and blend for about 30 seconds to make a smooth paste.
With the machine running, add 1 egg and blend.
Scrape down the side of the bowl with a bowl scraper, and then, with the machine running, add the other egg and mix well.
With the machine still running, slowly add the double cream to the bowl and blend to a smooth paste.
Decant the mix into a clean bowl.
Add the sauteed mushrooms, herbs and chopped pistachios and mix well.
Spoon a layer of chicken and mushroom mousse into the bottom of the lined terrine mould.
Build the terrine by adding a layer of cooked chicken breast and then topping with a layer of mousse.
Repeat, this time by adding a layer of the chicken legs and again topping with mousse.
Layer up, filling the terrine mould to use up all the chicken and mousse.
Once the terrine is filled, top with the remaining 3 slices of bacon, lengthways.
Place another sheet of clingfilm over the top, and seal with the overlapping clingfilm that lined the mould and create a seal.
Place the terrine mould into a bain marie [Note 2] allow the water to come about 1/2 way to the top of the terrine. Cover the whole lot with foil and seal the edges.
Cook for 1 hour or until the internal temperature is above 75c
Remove from the oven and carefully remove the terrine from the hot water - I use tongs and an oven glove. Discard the water and allow the terrine to come to room temperature.
Pop in the fridge overnight. then, remove the terrine from the mould and the clingfilm and slice into 10 x 1cm slices.