Preheat the oven to 450 degrees and set a rack on the middle level.
Slice off and discard the heels of the baguettes and cut them into 36 slices about 1/2 inch thick. Lay the slices side by side on a baking sheet, or two if necessary.
Mix together the meat, soy sauce, brown sugar and scallions in a large bowl with your hands. Knead thoroughly until you have a fine paste. Make 36 small meatballs about the size of a walnut. Put one in the middle of each bread slice, pressing down slightly.
Bake for 7-9 minutes until the meatballs and bread have become one.