AI was experimenting in the kitchen and made a chocolate version of my favorite cake. We ate several pieces of it, but due to diet issues nobody could eat any more. Not wanting it to go to waste, I offered it to anybody on my (personal) Facebook that wanted to come get it.

A relative of mine wanted it for her family. She came and got it and I haven't heard from them since. No "thank you" or anything.

The cake tasted good to us, but it was a tres leches cake and I know they're used to Walmart style cakes.

It just kind of bugs me that they never even bothered with a thank you. Should I send them a quick "Did you enjoy the cake? :)" or just let it go? What would you do?

   I probably would let it go, because they didn`t ask you to bake a cake for them. You offered them a cake that you can`t eat because you are on diet.

Did she say thank you, when she was picking up cake?

A

To be honest, I was hoping for some feedback on the cake which is another reason why I offered it to someone.

And no I didn't get one while she was here.

Kind of annoying.  Maybe next time when you're giving the cake away be sure and mention that you'd like feedback.

And plan to give it to someone whose opinion you trust.

 I didn`t see that tread went on. To OP: Oh, I understand you.

 I often bake and bring a cake to a family gatherings ( many relatives on my moms and my dads side).

                        There are 2 kinds of people of all my relatives:

ones that eat my cake and say right into my face that cake is so delicious.

others will dig every inch of cake and find that there is something wrong: the filling is too sweet or not sweet enough, the layers are thick or thin, too much icing and so on.

Just wanted to add that I never asked people/relatives if they liked my cakes or not, but good and bad feedback helped me so much to improve.

AIf it was something new I was trying I would ask for an honest feedback because I'm considering adding it to my line up. If it's a cake I already know people love I'd let it go. It seems your feelings are clearly not their priority and no more free cake for them!

yyou've got nothing to lose by asking for feedback. they aren't going to ask for a refund.

My guess is she's afraid they'll think she's hinting they should have said thank you if she asks . Just guessing though.

They're your family. Just ring and say I'm calling to ask about how you liked the cake because I'm thinking of adding it to my menu. Hopefully that way you won't sound like you're fishing for compliments if you ask them about texture, flavour, icing and cake combo (did it work? if not, why not?). 

From your post though (I could be wrong), it sounds as if it's thanks rather than feedback you'd like to receive. 

Agree with the above poster. If I gave away a cake and I already knew it tasted good, I wouldn't contact them again if they didn't get in touch. However, if I genuinely was wanting some feedback because it was a new recipe or whatever, I would absolutely shoot a note to ask if they liked it. There's no problem at all with doing that, in my opinion. Especially a non-paying relative.