In order to make the actual cake, I used the bottom part of a large cupcake mold similar to this one: http://www.walmart.com/ip/11969232?wmlspartner=wlpa&adid=22222222227008664763&wl0=&wl1=g&wl2=&wl3=18115491550&wl4=&wl5=pla&veh=sem
I used a box cake mix and baked two bottoms so the cake would be tall enough. Once the cake finally cooled, I layered the two cakes with frosting in the middle as a "glue" and then using a serrated knife, I cut around the edges to make the cake as even as possible.
I also used store bought frosting and went to Michaels and purchased the 1M Wilton tip to make the flowers. I followed the instructions on http://iambaker.net/rose-cake-tutorial/ to make the flowers. Surprisingly, the decorating part was the easiest/fastest!