There's already an ikura sushi cake tutorial on the Internet, and I followed the same basic principles but tweaked mine to make it look more like an actual piece of ikura sushi. Here's what went into it:
- Cake: Betty Crocker white cake mix. Two circular cakes with the edges trimmed off, layered. I used the trimmed edges to build the smaller cake, which you can see in the large picture.
- Buttercream frosting between layers and on the outside of the cake
- Shredded coconut around the top edge for "rice"
- Nori: Homemade fruit leather (like a Fruit Roll-up) made out of applesauce, pear, blackberries, and lemon juice with green food coloring. You could use store bought fruit leather if you can find the right color. There are also many recipes online. I used scissors to cut it to the right size.
- Roe: Jello molded in half circles. An egg holder or carton with rounded sections would be ideal for molding the Jello, but I couldn't find one, so I ended up using the blister pack from a multi-pack of small bouncy balls! The larger Jello balls ended up falling apart under their own weight, so I would recommend using a heavier gelatin mixture just for looks. However, the tropical fruit Jello tasted nice.
- Ginger: Apple sliced thin on a mandoline, soaked in lemon juice with sugar and a little red food color
- Wasabi: Buttercream frosting with green food color
- Soy sauce: Espresso with rum and sugar