Cut the bread shapes: Press a 3 to 4-inch bat-shaped cookie cutter into each slice of bread before adding any filling. Cutting first keeps the edges clean and the thin wingtips from tearing.

Layer the cheese: Place one slice of cheddar and one slice of American cheese between two bat-shaped bread pieces. Keep the cheese slightly inside the edges so it doesn't spill out as it melts.

Butter the outsides: Spread softened butter evenly over both outer faces of each sandwich, reaching all the way to the wingtips. This helps the bread brown evenly in the skillet.

Heat the skillet: Warm a nonstick skillet over medium-low heat for about a minute before adding the sandwiches, so the bread doesn't scorch before the cheese melts.

Cook the first side: Lay the sandwiches in the skillet and cook for 2 to 3 minutes, until the bottom turns deep golden brown.

Flip and cook the second side: Flip each sandwich carefully with a spatula and cook another 2 to 3 minutes, pressing lightly so the cheese melts all the way through.

Check the melt: Gently press the center of a sandwich; it should feel soft and give slightly, meaning the cheese inside has fully melted.

Transfer to a plate: Move the sandwiches to a plate lined with a paper towel to catch any extra butter, letting them rest for a minute.

Add the bat eyes: While the sandwiches are still warm and the cheese is soft, press two small black olive slices onto the top of each one for eyes.

Serve warm: Arrange the mini bat sandwiches on a plate or lunchbox tray while the cheese is still soft and gooey.