So we surfed the web, checked the recipes and design and after some thoughtful discussion we agreed on one design that I used as a model. She let me decide on flavor. I opted for a chocolate chiffon cake. I doubled the recipe so I could have 2 layers. I spread chocolate mousse filling on each layer of the cake and masked the entire cake with black buttercream.
The decoration took a while as I had to mix 9 different colors for the sun and each planet. To ease the trouble in drawing the planets, I piped the buttercream spirally. I used tip number 8 for the sun , number 6 for bigger planets and small tip for smaller planets. Had I known that the sun didn't look like how it was supposed to look like, I would have piped the buttercream using the star tip.
It was kind of difficult to get the right hue of black but I managed to arrive to the closest shade by mixing black with blue and adding a bit of brown. Using only black dye would turn buttercream into grey color.
The inscription said Spectacular Space.
So here's the space without the planets. It still looked grey but this was the darkest I could come up with. The buttercream was already splitting and it was not a good idea to add more color.
The space with the sun and the first four planets. The sun looked like just a big circle. I used the star tip to pipe the stars. Will do better next time.