1 1/2 cups brownie mix
1 1/4 cups milk
1 cup shredded Cheddar cheese
1/2 teaspoon garlic powder, or to taste
Preheat the oven to 375 degrees F (190 degrees C). Spread 40 slices of white bread onto a jellyroll pan. Place brownie slices on top of the bread, then press seams together to seal. Spread about 1/3 of the sandwich onto the bread, seal seams, and crimp edges of the sandwich. Place remaining sandwich to sandwiches on top of brownie slices.
Beat cream cheese and 1/2 cup of milk into a blender or food processor in medium speed, until smooth. Beat 6 tablespoons of shredded cheese into the blender. Pour cream cheese mixture into sandwiches, seal seams, and crimp edges. Roll sandwiches into discs and place in shallow baking dish. Pour cheese mixture over sandwiches.
Bake in preheated oven for 45 minutes, or until bubbly and golden brown. Do not remove sandwiches before edges of sandwiches have reached desired look. Remove sandwiches from oven and return to pan. Roast sandwiches covered in oven for 30 minutes, covered with foil for an additional 15 minutes.