Butter and flour an 8-inch-diameter stainless steel bowl.
Combine cake mix, water, oil and eggs in large bowl. Beat with a hand mixer or by hand for 2 minutes, or until well blended.
Transfer batter to prepared buttered bowl.
Bake for 45 minutes, or until a toothpick inserted into the center comes out clean. Cool cake in bowl on a wire rack for 20 minutes. Invert cake onto cooling rack and remove bowl. Cool cake completely.
Spread 1 can of frosting over rounded side of cake.
Mix remaining can of frosting with powdered sugar in large bowl and transfer to a pastry bag fitted with a star tip. Frost or pipe a rosette atop each cupcake.
Place a toothpick into the bottom of each cupcake; press toothpick into cake dome, forming a bouquet.