This treat is very easy to make, all the real effort goes into presentation. To make your own Rice Krispie sushi as shown here you'll need the following.
Marshmallows - white
Marshmallows - multi-colour
Fruit Jelly Candy
Sour Jelly Candy
Making Rice Krispie treats is strait forward, just melt butter and marshmallows together, then add Rice Krispies. Forming the treats into sushi shapes takes a little dexterity. To produce California Roll shapes first roll some Rice Krispie treats out into a sheet, then place a column of large marshmallow in the center and wrap the warm treat around the marshmallow. Place this roll to the side in order to allow it's shape to set. Once firmed up, wrap the roll with fruit rollup sheet (or fruit by the foot or other similar product). Now you may slice the roll with a sharp knife into discs. Add a fruit jelly candy to garnish :)
The rice rolls are much easier to make, just take a hand full of warm Rice Krispie treats and shape into an oval shape. Use the handle of a spoon to create an indent in the middle of the treat in order to place candies or colored marshmallow filling. Then use fruit wrapping to bound the treats together.
To complete the sushi appearance you may place pieces into a small box and wrap with a bow (including chop sticks), or arrange as a platter.
I hope you enjoy making these treats too!