I need to feed 150 via sheet cakes for a wedding, I have sheet cakes pans in size 11x15 and 9x13. I have looked at the wilton book I have a guess on the serving sizes but I don't believe that people ever cut the cake along with the wedding cake guide. What sheet cake combination would you make? There is so much difference between the party serving size and the wedding size. I think three 11x15's will be too much cake but I'm not sure. Any advice and ture serving measurements would be appreciated.
The Wilton wedding cake chart is pretty much the industry standard. As leahs says, use anything other than that (Wilton party chart, Earlene's chart) and you're GIVING AWAY cake. I always use the Wilton wedding cake chart to figure servings and I charge based on that number.
I assume you're making a single layer 11x15 cake that's 2" high. A standard serving is 2x2 square. According to the Wilton chart, an 11x15 is 35 servings. Three of those will only be 105 servings. For 150 people, you could do two 9x13s and three 11x15s for a total of 154 servings.
For weddings, I do kitchen cakes that are two layers high with filling in between. These are 4" high when iced, and a standard serving is the same as any other two-layer cake - 1"x2"x4". An 11x15" kitchen cake is roughly 77 standard servings. If you did two 11x15 kitchen cakes (2 layers each), that would be 154 servings.
It depends on what you mean by sheetcake. If you are making a one-layer 11x15 cake, you will need four of those. If you are making a two layer 11x15, that would bring the height up to 4 inches. At 1x2x4, you would get about 82 wedding slices, requiring two of these layer cakes. You would have 14 extra slices.
Go by the Wilton chart. If people don't eat their cake, it is a smaller wasted slice. And take it from someone who always eats the left over slices at the table, people will have enough cake.
I would suggest the two cakes since they will be easier to transport. Four singles take up a lot of room.