Erlenmeyer flask - Shaped Cake

when you determine servings it's by the footprint of the cake

so i think a 6' is gonna be starting too small since it's so carved away up above (6" is only 14 servings)

i think i'd do a 7" or 8"  cake and  that should make enough servings with all the extra bits

so it needs to be about 7- 8 inches tall not including bubbles

i think i'd do the top 3-4 inches in rice krispie treats or some carved cake and a cupcake

i would do '2-tiers' with the board & dowel due to the height and to prevent the potential to be woggly

(spell check does not think woggly is a word--phffft)

(they never made a erlenmeyer flask!)

you could roll some fondant balls or pipe some big dots blobbing out

you could pipe them with just a coupler on the piping bag for the big ones and use varying sizes of tubes

but that one big bubble could be the the top of another cupcake

a smoke machine or dry ice would a cool addition to this cake--i've never used anything like this--just conjecturing

the closest i ever got would be using those 'snake' fireworks that it's like this little gray mini-marshmallow sized thing and you light it and this huge long continual stream of 'smoke' or whatever keeps coming out of it

might kinda burn the cake but would be cool (again just an idea i've never done it)

http://www.google.com/search?q=fireworks+snakes&hl=en&tbo=u&qscrl=1&rlz=1T4ADBS_enUS275US275&tbm=isch&source=univ&sa=X&ei=RvcWUbPNHo269gSfo4CoCw&sqi=2&ved=0CEcQsAQ&biw=1280&bih=834#imgrc=fkJhY09y9ceklM%3A%3Bsnr0WaSFeiKZhM%3Bhttp%253A%252F%252Fwww.allsparkfireworks.com%252Fblog%252Fwp-content%252Fuploads%252F2011%252F03%252Fblog-firework-snake.jpg%3Bhttp%253A%252F%252Fwww.allsparkfireworks.com%252Fblog%252Fmake-your-own-black-snake-firework-noveltites%252F%3B450%3B338

The top area and the bubbles are just fondant dusted with edible pearl dust.

You should assume you will waste 1/3 of the cake in carving the tapered part.

I would use a good solid layer of buttercream between the cakes, and chill overnight before carving.  Because this is tapered at the top, I wouldn't worry about boards between layers.  If possible,  keep it chilled until it gets served.