Preheat oven to 180 degrees.
Place leek and garlic into bowl. Blitz on speed 9 for 5 secs.
Meanwhile, cut up chicken into bite size pieces and coat in season all.
Once onion mix is finished, add bacon and oil and cook at 100 degrees, speed 2 for 5 minutes.
Attach butterfly attachment.
Add chicken and cook at 100 degrees, reverse, speed 2 for 5 minutes.
Open lid and scrape the chicken off the butterfly and scrape down the bowl. Leave butterfly in.
Add sour cream. Cook at 100 degrees, reverse, speed 2 for 15 minutes. In the last 4 minutes add the mushrooms, cheese and pepper.
Slice each puff pastry sheet in half.
Place a little of the mix on one half and fold over. Seal the sides.
Repeat for all. You will get 8 parcels from this mix.
Brush with a little beaten egg and sprinkle with sesame seeds.
Bake for 30 minutes or until golden.
Whilst they are baking I make mash in the tmx and steam some carrot and asparagus to serve with it. Salad on the side also works well.