Spread the softened butter over the surface of the dough circle, keeping about ½ inch of the edges free of butter and the other ingredients.
Sprinkle the salt over the butter.
Layer the pancetta over the top of the butter.
After cleaning the fish, rinsing well and drying with paper towels, lay the filets on top of the pancetta and sprinkle with a little sea salt. Be careful not to oversalt this dish.
Wet the edges and roll the dough circle into a cylinder. Make sure all the edges are sealed well.
Place the roll on a parchment lined cookie sheet.
Turn on the broiler to high, place the sheet under the broiler and brown the top of the roll. Watch carefully so this does not burn.
Once browned turn the oven temperature to 200 degreed F.
Bake for 5-6 hours.
Some recipes suggest placing a moist towel over the roll to keep the dough soft. I prefer a crunch crust, which is why this recipe is laid out as above.
This can be served hot from the oven, or at room temperature. I prefer this hot from the oven.
Some recipes use a non-yeasted dough, I much prefer the yeasted dough. At 200 degrees there will be some rise of the dough.