I have someone who has ordered a cake for a retiring teacher in two days and has requested that the cake serve 30 people which would be a half sheet...correct? What worries me is that I know that she is expecting to be able to cut larger pieces and a half sheet would not yield larger cuts for 30 people. I'm tempted to do a full sheet, but she hasn't paid for it. I'm concerned that when she sees the cake that she'll say that it isn't big enough. How do you all approach these issues?
When folks place an order, I give them options. I usually list the size and number of servings as well as the size of each piece. This allows them to make the decision.
NEVER make a cake without payment up front!!!!!!!!!!!!!!!!!!! I can't stress that enough. There are countless threads here of hard-working people getting screwed or taken advantage of because they didn't get the cash before agreeing to make the cake.
Second, I don't know what serving chart you are looking at, but this is industry standard...
It's not your problem on how big they cut the pieces. You tell the customer, "this is the size of the cake, this is how many servings it has". If it's not enough then they need to pay for more cake. You don't just give them more!
Don't take this the wrong way, but if you are doing this as a business and you have these questions, how are you making any money? And if you are new, then these are things you need to learn real fast - working for free, or paying people to eat your cake because you aren't valuing your work and not charging accordingly... REALLY sucks!
Your cakes are really nice, BTW... really pretty!!! Don't undervalue yourself!
Your teapot cake is exceptional.
OK, I'm done gushing.
An 11x15 single-layer 1/3 sheet serves 35-37 industry standard 8 cu. in. servings (2x2x2):
An 11x15 single-layer 1/3 sheet cut to larger party servings which are 50% bigger 12 cu. in. servings (1.5x2x2) would still serve 30: http://www.wilton.com/cakes/making-cakes/baking-party-cake-2-inch-pans.cfm
So, no... I wouldn't use a 54 serving half sheet, nor a 100 serving full sheet cake when the 1/3 sheet is more than enough either way it's sliced.
You need to tell her it's big enough, explain the portion size, and if she's still wanting larger slices--she'll need to pay for a larger cake and expect leftovers.
Make sure to charge for the 35-37 slices regardless if she's cutting it into only 30 larger slices.