When I first started making this terrine you couldn’t buy minced chicken, so there was no alternative but to drag out the mincer and process the chicken and veal yourself. Since those days a blender or pre-minced chicken make it a bit easier. I think if you’ve got the time mincing up the chicken breasts and veal yourself is the best option, as you get a better quality mince, but if you don’t have the time give pre-minced a go. The finished terrine tastes really good and is worth the effort either way.