Start by cleaning the chicken livers - you want to get rid of any bits that may become tough. Find any white fat or connective tissue on a piece of liver and hold on to it as you use use your knife to take off the liver flesh. Remove the fat/connective tissue and roughly chop the liver. Repeat with the other pieces.
Peel and finely dice the shallot and garlic. Warm ½tablespoon (6g) butter in a skillet/frying pan over a medium heat and add the shallot. Cook, stirring, for a minute, then add the garlic.
After another minute or two, as the onion is starting to soften and become translucent, add the liver and thyme. Cook for around 3 minutes on each side until lightly cooked on the outside but still pink in the middle.
Add the brandy to the skillet/pan and stir gently to help the brandy evaporate off the alcohol and reduce. After a minute or two it will become almost syrup-like, then remove from the heat.
Scrape the contents of the skillet/pan into a food processor and add the remaining 2tablespoon butter. Blend until the mixture is very smooth. If you want an extra-smooth pate, then press the mixture through a fine mesh sieve.
Either way, then transfer the pate to two or more small ramekins/dishes and flatten the top. If you don't want to top with butter, place cling wrap/film over the top of the pate, pressing on to the surface and ideally then also cover with a lid. Refrigerate and use within a day or two or freeze until needed. If adding butter, cover and chill in the fridge to firm up for around 25-20 minutes.