On a large cookie sheet lay your pancetta out. Bake for about 7 minutes or less, depending on your desired crispiness.
While pancetta is cooking, brush one side of each piece of bread with butter then slice tomato
when pancetta is done, take out of oven and and put bread in and lightly toast. watch carefully so toast doesn't burn.
When toast is done, on toasted side of bread add all ingredients in this order: cheese, pancetta, tomato, cheese.
on a medium heated griddle or skillet, pour a little of the melted butter on griddle or in skillet add sandwich on the un-toasted side, make sure to butter side you will flip, takes a little skill to keep sandwich together, but it can be done!
continue with steps until all sandwiches are done. you may serve each sandwich as they come off of the griddle...enjoy