Arrange 8 slices of bread on a board and spread with Chocolate Snack Spread, about 1/2 tablespoon per slice. Flip all of the slices and spread half with marshmallow fluff. Spread the remaining 4 slices with Chocolate Snack Spread, about 1/2 tablespoon per slice.
Sprinkle 2 tablespoons chocolate chips over each slice with chocolate spread. Arrange sliced bananas on top then cover with remaining bread, marshmallow fluff side down.
Heat a large skillet over medium heat. Carefully transfer a sandwich to the skillet, cover and cook until bread is crispy and chocolate is starting to melt, about 3 minutes. Flip the sandwich, re-cover the skillet and cook another 3-4 minutes, until chocolate is fully melted and marshmallow is gooey. Transfer to a plate and serve hot. Repeat with remaining 3 sandwiches.