Heat 15g/½oz of the butter in a frying pan until foaming.
Add half the livers and fry quickly on all sides until golden, but still pink in the middle, about 4-5 minutes.
Repeat with a second batch of butter and livers.
Place the livers and juices in a food processor.
In the same pan heat another 15g/½oz butter, add the shallot, garlic, and orange juice and zest and cook over a moderate heat until the shallot is soft but not coloured.
Add the orange liqueur and freshly ground black pepper, and scrape the bottom of the pan to release any coagulated juices.
Place everything in the food processor, including the remaining unsalted butter. Blend until smooth.
If you want a very smooth pâté, pass the mixture through a fine sieve and put in a bowl. Cover with the cling film, cool then refrigerate. If not using within 48 hours, cover the top with clarified butter.