Add the matcha powder and cream cheese with the warm rice. Add salt and pepper to taste. Mix well.
Divide the rice into 3 equal-sized balls.
Lay out a piece of plastic wrap and place a rice ball in the center. Lift and hold the four corners of the plastic wrap and twist. Form the rice ball into a sand bag shape. Repeat to make 2 more rice balls.
Cover the rice balls with sheets of prosciutto ham.
Decorate the rice ball with the cream cheese using a decorating tube or spoon so it will look like a cupcake.
Roll up a strip of prosciutto. Pin a boiled edamame at both ends of a stick of spaghetti to imitate a rose flower.
Place the prosciutto rose on top of the cupcake rice ball and serve.