Step 1

Lay each chicken breast between 2 pieces of clingfilm and bash with a rolling pin until 2cm thick.

Step 2

Add to a bowl with the buttermilk, cover and chill for at least 2 hours but preferably overnight.

Step 3

Mix the flour, oregano, paprika, cayenne pepper, garlic powder and some seasoning on a large plate.

Step 4

Remove the chicken pieces from the buttermilk and dredge in the seasoned flour, shaking off any excess.

Step 5

Fill a large pan no more than a third full with vegetable oil and heat to 175C or until a piece of bread browns in 40 seconds.

Step 6

Cook the chicken, in batches, for 4-5 minutes turning half way, until deep golden brown.

Step 7

Drain on kitchen paper and keep warm while you fry the rest.

Step 8

Spread a dollop of chipotle mayo across one bun half and a dollop of guacamole on the other.

Step 9

Pile up the sandwich with lettuce, streaky bacon, gherkins and chicken and press together.