Pour Beef Broth in sauce pan and heat to boiling.
Boil for 5-10 minutes to remove some of the extra water from the broth to make it a little more flavorful.
Set oven to Broil.
Slice the buns in half and place open on a cookie sheet.
Place some sliced roast beef on one half and place a slice or two of Swiss cheese on top.
Leave sandwich open.
Broil for 30 seconds - 2 minutes checking CONSTANTLY so it doesn't burn.
As soon as it looks nice and toasty golden brown, close the sandwich by placing the top of the bun back on the sandwich.
Continue to Broil again for an additional 1 minute or so until the tops are nice and golden brown too.
Serve with Broth!