Line an 8 x 8 inch baking dish with parchment paper making sure the edges come up on two sides.
Spread the softened ice cream evenly in the lined pan and place in the freezer overnight.
Break the graham crackers in half so that you have 18 squares.
Using the edges of the parchment paper, lift the ice cream on to a cutting board.
Slice the ice cream into 9 equal squares and sandwich between two graham cracker squares. If desired, spread melted chocolate on all the graham cracker squares and press the chocolate side onto the ice cream.
Place the ice cream sandwiches back in the freezer for at least 10 minutes before serving.