Wow! I found this recipe over at a wonderful blog called "The Girl Who Ate Everything" and it blew me away from just a photo! Below is her recipe along with some comments and suggestions from my own baking experience.
1 unsliced loaf sourdough bread
12-16 ounces Monterey Jack cheese, thinly sliced (and believe the recipe when it says thin sliced...if you don't you will have burned bread and lots and lots of cheesy globs stuck in it)
1/2 cup butter, melted (it will not look like you have enough butter, but do not add more)
1/2 cup finely diced green onion
2 teaspoons poppy seeds
Preheat oven to 350 degrees.
Cut the bread lengthwise and widthwise without cutting through the bottom crust. This isn't as hard as it looks, it is fairly easy. Be sure that when you are cutting the squares that they are large enough to get a good grip on when pulling apart the bread
Place on a foil-lined baking sheet. Insert cheese slices between cuts. Combine butter, onion, and poppy seeds. Drizzle over bread. Wrap in foil; place on a baking sheet. Bake at 350 degrees for 15 minutes. I found the need to bake for nearly 1/2 hour.
Unwrap the bread and bake 10 more minutes, or until cheese is melted.
This is a wonderful recipe! I've read on many review sites that it is great to take to potlucks and parties, but I wouldn't do that. Imagine everyone else at the gathering picking through the pieces and getting their germs all over everything! Who knows where those hands have been! Gross! (Okay, I'm really not the only one who thinks of things like that, right?) My recommendation is to make it at home with your family, make sure everyone washes their hands well and enjoy!