Just in time for the end of the year, here's a New Year's Eve/holiday season one-shot story set in the same story universe as "Chuck & Sarah vs Their Next Adventure". The timeline of multiple stories is on my FFnet profile page. If you haven't read that story, it's my 5-part, 29 chapter post-finale story. (I wrote two parts/13 chapters, in 2012. starting immediately after the fade-to-black. Instead of writing sequels, I three more parts and 16 chapters in 2019.)
This story is set between the "compatible" Castle/Chuck crossovers, "Chuck vs 3XK" and "Chuck vs the Hunt", posted in 2019. I made an comment in the second of those stores, the origins of which are in this story. The story makes no reference to Castle, so whether you read those is up to you.
This story...
For the first Christmas after the beach, Sarah and Chuck Bartowski didn't have a viewing marathon of episodes of The Twilight Zone. Worried that she had messed up tradition, Sarah's determined that they have a marathon on New Year's Eve. This story is set in the some story universe as "Chuck & Sarah vs Their Next Adventure" https://www.fanfiction.net/s/13783766/1/Sarah-vs-The-Twilight-Zone-Marathon