Driving to Trikala from Athens after a long flight, looking for a place in between to stay for the night, grab some great authentic food and then head out in the morning for a nice ride to the city.
Any suggestions?

After a long flight, it might be a good idea to go by train: Airport - Proastiakos - SKA - Intercity train - Paleofarsalos - local train - Kalambaka
or by bus from Athens bus terminal B

There are not many nice places on the way to Trikala from Athens
Chalkida, a nice city in Evvia, is too close to Athens and Volos, which could be another option is too far away.....

Lamia is in the middle of the route but not particularly worth seeing but Kamena Vourla might be ideal for an overnight.

It's a nice place on the sea, with a very long sea promenade and many restaurants and smaller hotels. Not much to see other than the sea view
from your hotel, but in my opinion that's the best place to stay if you'd like to split the drive.

If there is any chance that you will have jet lag, I would strongly encourage you to take public transportation for your first night or two. Although many people are not aware of it, there is mounting evidence that driving with jet lag is just as dangerous -- to yourself and others -- as driving drunk, and nothing you can do will prevent the microsleeps (which you might not even notice) that are the apparent culprit. Seriously -- NOT a good idea, no matter your other constraints and no matter your prior experience! And please be patient with me if you think I’m being overly adamant, but I know too many people who have died or been seriously injured in accidents to which jet lag was a contributing factor, and I know too many people who will spend the rest of their lives dealing with the knowledge that they were responsible for accidents that resulted in multiple deaths, including those of children, all because they were too confident in their ability to drive safely with jet lag. The issue has become a bit of a cause célèbre for me….