“It was vanilla.
The secret recipe for the cake was vanilla.”
I decided to round up some of the best answers:
1.

“A John Grisham character getting a bagel at Cafe du Monde in New Orleans.
But, in real life they only serve beignets and those are nothing like bagels.”
Powdered sugar donut would be less egregious!"

u/BeeBayou
3.
Did they even look at a map of the state?"
u/marshmallowkorok
“Without interstate highways at that time, it would have been an 8-10 hour drive.”

Bangor and Castlerock are also mentioned in the book."
“The main character and love interest were both children of musicians.
Love interest’s name?

I just could not take it seriously.”
u/RagingAardvark
6. u/SF_Bluestocking
7.
What are you drinking to have it hit you that hard that fast?!"

u/dinnie450
9.
“I read a historicalromance novelonce where the love interest was supposed to have slept with 5,000 women.
Even as an American, I know the singular form of ‘pence’ is penny.

So, this rare and pricey metal is used for train tracks for miles and miles?”
u/awcomix
12. u/BulldogsOnly
13.
“When authors have a Latino character pepper their dialogue with random Spanish words.

We don’t really do that, especially when among non-speakers.
This was in the late ’70s, and that was not a visible detail in ultrasounds back then.”
u/Togekriss
15.

It is a full on warm, orange red.
Nothing cool toned about it."
u/Pristine-Fusion6591
16.

“Most books that use horses as transport.
They cover large distances, rarely go lame, and can always find food for them.
They need to eat for hours, sleep, and carrying oats is not particularly practical.”
u/bohorose
18.
“InThrone of Glassthe character says ‘I’m going to stay in this competition’ and resolves herself.
You had the same resolution happen twice.
CUT ONE OUT.”
u/dreamingrain
19.
“A book where the main character was a baker.
The secret recipe for the cake was vanilla.
I was so mad, it’s all I could think about for the rest of the book.”
“It was a thriller about a woman escaping an abusive relationship by moving to Cornwall or somewhere similar.
u/David_is_dead91
21.
“When someone lowers their voice ‘a few octaves’.
That’s a lot lower than you think!”
H/T tou/korehananandr/booksfor having this discussion!
Note: All submissions have been edited for length and/or clarity.