
For someone who cooks for a living, it is a challenge to calculate how much to charge for the food I prepare. Rule of thumb in the industry is to keep the food cost below 30%. I normally try to figure out how long a dish will take to shop and cook for, then come up with a price and try to spend no more than a third of what I will be paid. Sometimes it works, sometimes it doesn't; potential clients often don't realize how much time it takes to prepare the food. I shop, prep, cook, package, clean, and most of the time deliver. There is also the hidden costs of the gas, electricity, and water bills, which are impossible to estimate. Often I make one of something, so I can't save on volume, and obviously my ingredients are more often than not purchased at a retail price. Take this cake for example:

I made it for a fund raiser event for which I donated 6 desserts. The person who bid on the item asked me to make a birthday cake. Since I don't know the woman I am baking for very well , and since she doesn't like chocolate, I decided to make this crowd pleaser, easy to make and fast to decorate cake. I have a rough idea of how long it took me to make; about 15 minutes to make, 15 to assemble, and 15 to decorate; totaling 45 minutes, not including shopping and delivery.
This is what I spent:
Sponge Cake $2.5o
Simple syrup $0.10
Pastry cream $1.50
Heavy cream $2.65
Strawberries $1.50
Marzipan $2.00
Chocolate $o.38
Sliced almonds $2.00
Grand total: $12.63
If I applied the 33% rule, I would charge $42, for a gross margin of $29.37. The cake serves 8 to 12 people, which means $3.50 to $5.25 per slice. What do you think? Is $42 a fair price?