Sauté the onions in butter til translucent, set to the side.

In a bowl mix in everything including the onions, except for the bacon and the extra melted butter. Don't over mix it or it will affect the end result.

Lay bacon down on foil to make a blanket.

Form the meat mixture in desired shape and wrap the bacon around from underneath to seal. You might need to add more on top. Do so in a cross like pattern.

Brush it with some of the butter and cook it in the over at 200 degrees celsius for about 1 hour until 75 degrees celsius internal temperature.

Brush with butter every 15 minutes or so with your remaining melted butter.

Let it rest for about 15 mins before cutting into it.