Now, you've got a little problem. The mommy-to-be absolutely adores sushi but you know that she can't have any raw food while she's pregnant! What can you do to help her get over this craving? Why don't you adapt a Japanese birthday sushi cake and make it into a sweet one? While it won't really relieve the craving, the cake can come with a promise to bring her to a sushi bar once her ob-gyn says it's ok.
The first thing you need to do is make the sushi toppers for the cake. Your main ingredients here are fondant, cereal rice treats, and paste colorings. Other ingredients are dried mango and papaya slices, fruit leathers, and baby jelly beans and gummy worms. An invaluable asset would be a sushi cookbook so you can copy exactly how the sushi looks and a bamboo mat to press the sushi rolls.
Knead the fondant and using a toothpick, slowly add the paste coloring until you get the desired shade. Make sure your kneading surface and your hands are very clean since fondant picks up everything! Dust the surface with sifted cornstarch to keep the fondant from sticking.
The colors of the fondant depend of the type of sushi you're making. For example, you need green fondant for the wasabi, dark green fondant for the nori seaweed, and a red and white fondant for the kani or crab sticks.
To make tuna sushi, lightly coat a dried papaya slice with oil and massage it a bit to make it shiny and supple. Form a ball of rice using the cereal rice treat, pressing it firmly to make it stick. Top it with the papaya slice and you're done. You can also cut a slice of fruit leather to go over the sushi and hold it together.
A california roll needs a thin sheet of dark green fondant to start. Roll it out very thin on plastic wrap or parchment paper and trim with a sharp knife to fit in the bamboo mat. Take apart the rice treats and spread it over the fondant sheet. Stuff the “sushi” with strips of oiled dried papaya and dried mango, green and yellow gummy worms to simulate cucumber and yellow preserved radish, and the red and white fondant kani. Line the bamboo mat with plastic wrap and lay the whole thing on top; roll up starting on one side, while slowly peeling away the plastic wrap to make sure it doesn't get eaten into the sushi roll. Press it down firmly so it holds together. Let it rest for a while and then cut it with a heavy, sharp, oiled knife.
To simulate the wooden serving board, knead together three balls
of fondant, one tinted dark brown, one light brown, and one white.
Don't mix all these ingredients together! Roll it out to about an
eighth of an inch and use it to cover up the cake. Set your sushi
on top, with wasabi and a few petals of pink fondant to look like
preserved ginger. Arrange an opened pair of chopsticks on the birthday
sushi cake.