I have no idea about laws in the UK...Here in the US, you would need to take ALL correspondence from her, phone messages, emails, text messages, etc and gather them all together. 

Then you would sue her for nonpayment and a judge would rule that she owes you for the cake and court fees.

Good luck dealing with this asshat!

she has some serious stones for thinking she can stiff the boss's daughter.  I hope that presenting the invoice, again, and again, and again until you get payment will work.  I wouldn't normally think to hit her in her personal life for a business transaction, but I wonder if your mum could offer her overtime or make a comment or two about her knowing that she had unpaid wedding bills. 

At least you have reason to go by her place of work to hand deliver invoices while visiting your mother.  I'd also frankly and firmly let her know that this isn't going to go away. Then give her a mad dog stare down.  (but I'm in a bit of a mood today, so take that last part with a grain of salt LOL!) 

I'd definitely take her to the small claims court and add on any fees to what you're claiming from her!

In fact, doesn't she automatically have to pay if it's found in your favour??

Ahere is some info about suing:

You can sue and use the witnesses, either live or by affidavit (sworn statement) in small claims court. I would suggest sending a certified letter to the person who owes you the money, making the demand first. If they write back, then you might get confirmation of the money owed. The challenge is, even if you win, collecting the money. You can garnish wages and there are limited things of personal property you can seize. You might be able to put a lien on a house, depending on your state. So you might end up with a piece of paper that confirms they still owe you money, but that may not get much. Sometimes you can turn that over to a collection company and they will purse it for you for a percentage. I would sue them, assuming it hasn't been years because the time limit may have run. A lot of small claims courts have advisors about the process, not the actual suit and your library may have a small claims book.

OP is in the UK so likely that the rules are different anyway

A

Yes very true my main pointI want her to get is if she is going to sue make sure she is legal because that can open a whole new can of worms but she is not in US anyway so it probably doesn't apply

In the UK, home cake/catering businesses are permitted - you just need to register with your local authority and they will come and inspect your premises.  From what I've managed to glean from CC, it's not as difficult as it can be in the US.

I actually like the cake design, it's weird but I've seen weirder, and weird is interesting.

I'm interested in seeing what the bride's response is, especially since your mother is her boss. Who tries to skip out on a bill with that connection? What a moron.

I like the cake. And I think you did an excellent job. I definitely would not use my mother's position to help with the situation. That would be totally unprofessional on the part of the OP and her mother. You do not bring personal issues into the workplace. While it may be a business issue for the OP it most certainly is not for the mother. If that were to happen I think the cake snake (term borrowed from another CC member) would have every right to file a workplace grievance. Plus as a big girl with big girl panties (bigger than I like to admit) I can fight my own battles without my mommy.  And I am sure OP can too. I have filed a civil suit against someone before, not cake related. I knew I would not get my money...but what I did get was smug satisfaction knowing that a judgment will follow them for a minimum of 7 years. No buying a house...buying a car at 19% interest. Probably petty but it made me feel better....

BatterUpCake: IMHO, you hit it right on the head here - couldn't be more right... please don't mix the two scenarios - the cake and the mom's position.  Not an issue for the workplace, as it is totally unrelated; and not fair to the mom, as supervisor.  That's gonna totally backfire.  I have faith that that the OP will handle this in the most professional and appropriate way, whichever way they feel will settle it.  The OP will come away with head held high, I can just feel it.  That cake was well done, in that it came from someone's creative place, whether the bride's or the cake professional's - I applaud the final product.

Funny..today I was working on my school application and it asked me to describe professionalism. I can't find the words. I know what it is NOT though.

BatterUpCake:  the words decorum, demeanor, respect, and integrity come to mind...  but you already know those..  :)  good luck on your application!
 

The thing is I already got my acceptance letter. They kind of pushed things through for me. So now this is all a formality and I could write anything. But I have this horrible disorder that makes me try to excel at everything I do...lol. Really complicates life! lol They taught me when I came in the Navy "if you have to be a toilet scrubber, be the best damned toilet scrubber there ever was! Every job is important!" I am really going to miss certain aspects of that career....feeling all nostalgic tonight

LOL...