Combine almond paste, confectioners’ sugar, and corn syrup in a large mixing bowl.
You may need to work the mixture with your hands to ensure that it is well mixed. To prevent the mixture from drying as you work with it, rub hands with a light coating of vegetable shortening.
Form into a square or rectangular shape and wrap tightly in plastic; refrigerate until ready for use. Can be sliced for a simple, delicious treat or used to make decorations.