I first used a Wilton Stand-up Teddy Bear Cake pan and a round cake pan using 2 boxes of yellow cake and 1 box of strawberry (for the tail). I substituted 1 cup buttermilk (per box mix) in place of the water called for on the box. (Please note: this is less than the required amount of water.) I also used 4 eggs (per box) instead of what is called for on the box. This makes for a very moist but more firm cake that withstands the decorating. Trust me, the cake was very moist! I baked the cake according to the directions for the cake pan and let cool. Since I baked the day before, I covered the cakes with plastic wrap and aluminum foil and left on the counter.
Once I was ready to start decorating, I cut off the teddy bear's ears and cut a half moon shape out of the round cake for the tail. I covered cardboard with aluminum foil and used frosting to adhere the cake to the board. I also used frosting to adhere the tail to the body and cut several wedge shaped pieces from the unused portion of round cake to build the tail up to the body. I, then, used can vanilla frosting and added enough food coloring to make it the desired color. (I do recommend making your own buttercream frosting. The can stuff was too soft and would get too warm too quickly. I had to keep putting in the fridge to harden up.) I put a star tip in the corner of a quart sized freezer back and place the frosting in using a spatula. I refilled my bag as need. I squeezed stars all over the place. For the ruff, I used butter wafer thins. I cut slits in the back of the head and inserted 3 wafers. I then covered with frosting and used vanilla frosting and white chocolate chips for the tips (I used Cera from Land Before Time as a guide).
I used chocolate frosting for the outlining. I dipped the end of a sugar cone in white chocolate and let dry and used for the nose horn. The eyes are the bottoms of chocolate chips and the toenails are bottoms of white chocolate chips. I used a different color frosting for tummy, around eyes and bottom of feet.
The Triceratops Birthday Cake was super moist and yummy. The frosting did get a little hard since it took me so long to decorate 2 cakes? yes, 2 cakes. Please see stegasaurus cake link for a picture of the other cake.