Line an 8x8-inch pan with foil, leaving a 2-inch overhang on two opposite sides for lifting later.
Arrange 5 whole graham crackers on the bottom of the pan, breaking crackers as needed to fit.
Place one 11 oz. caramel piece in a microwave-safe bowl. Microwave in 30-second bursts, stirring between each burst, until the caramel is smooth and pourable. Pour and spread the melted caramel evenly over the bottom graham crackers.
Place a second layer of 5 whole graham crackers on top of the caramel, breaking crackers as needed and pressing lightly to level.
Place the 16 oz. Dove Dark Chocolate in a microwave-safe bowl. Microwave in 30-second bursts, stirring between each burst, until the chocolate is fully melted and smooth.
Transfer about one-third of the melted chocolate to a separate small bowl and set it aside for the final topping.
Stir the 2 cups mini marshmallows into the remaining two-thirds of the melted chocolate until the marshmallows are evenly coated. Spread this marshmallow-chocolate mixture evenly over the second graham-cracker layer.
Place the final layer of 5 whole graham crackers on top of the marshmallow mixture, breaking crackers as needed and pressing gently to level.
Melt the remaining 11 oz. caramel piece in a microwave-safe bowl in 30-second bursts, stirring between bursts, until smooth. Pour and spread this melted caramel evenly over the top graham crackers.
Pour the reserved one-third of melted chocolate over the top caramel and spread to cover. Refrigerate the pan until the layers are set (about 1 hour or until firm). Use the foil overhang to lift the slab from the pan and cut into bars.