Cream shortening (or butter) and sugar together. Add beaten eggs and melted chocolate.
Sift dry ingredients together and add alternated in thirds with the carbonated beverage (mix vanilla into orange soda). Beat thoroughly until batter is smooth.
Bake in a greased, floured 8x8x2inch or 9-inch square pan in the oven at 350 degrees or 40-50 minutes. (*note: my cake was baked in 32 minutes, so check early!)
Cream butter, and add sugar a little at a time alternately with the orange soda. Add orange rind and yellow food coloring. Add a few drops of red until the frosting is orange. Beat vigorously until light and creamy and can spread easily.
Cream a small portion of sugar with butter. Add orange soda drop by drop alternately with remaining sugar. Add vanilla and melted chocolate. Stir until spreading consistency. Lay cut-out of a cat on top of frosted cake, draw around it with a toothpick. Remove cut-out and outline with thin line of frosting Fill center of cat and spread out with thin knife to the edge of the outline. Add two bits of orange frosting for eyes or use two small green gumdrops.