The stuffing I made at the weekend was similar to this one. As I wrote earlier, you do not have to be at all precise about quantities: all you are doing is binding breadcrumbs with egg (and with the butter you may have used to soften onion and garlic), and flavouring them with as large a quantity of herbs as you like. I think that lemon zest is a winning addition.
This time, I used three thick hunks of white bread, which I whizzed with the leaves from a stalk of rosemary. I softened two small onions and a clove of garlic in about a tbsp of butter for only about five minutes, until they had started to turn golden. I added a handful of tarragon, chopped, and the zest of a whole lemon, with just a little salt (bread is salty) and generous grindings of black pepper. I mixed everything by hand with one beaten egg.
I put the stuffing inside my chicken. I can see the point of cooking it apart; but it stays moister inside the bird.