I made a cake this weekend, the cake itself turned out perfect, for once I was happy it with.
But I had this feeling that something was wrong and I just could'nt place my finger on it.
For awhile I was convinced there was a hair in it (thats one of my biggest fears, even though I wear a hair net and a baseball cap!)
I could'nt figure it out, so I delivered the cake with my fingers crossed, well it turns out I forgot to put the "Happy Birthday" banner on the cake. The customer specifically asked for it and I forgot it.
And on top of that she tipped me 25$ on top of the price of the cake.
I feel so bad, I told her she can have a discount on the cake, but she had already written the check out and told me not to worry about it.

So my question is, should I offer her a discount on the next order (assuming she orders again from the forgetfull cake lady), or should I just send her a free surprise cake, I have delivered to her work before I could just drop one off ?
Or should I mail her a check with a partial refund?
I really strive to keep my customers happy and its eating me alive that I messed up.

I would offer her a discount. I SCREWED up big time with an order and offered her a 50% discount on her next order (yes, I know VERY generous), but she said it was fine.

Did you charge her extra for the banner? If so I would refund the amount for the banner and maybe like 10%. I wasn't able to to this design feature on a cake once and I called the customer and told her and discounted the price of that design element.

I agree- offer her a discount on her next order and chill out. You do wonderful work. She'll be back.