The Christmas Caper by Gigi Pandian
Edinburgh at Christmas sounds wonderful. In this short story, Tempest is asked by her grandmother's friend to figure out how a painting was stolen from a museum, a seemingly impossible crime. The plot is pretty straightforward, but I loved the setting. The author does a fabulous job at bringing Edinburgh and its Christmas market to life. I would really love to visit sometime. One of my favorite fictional bookstores even gets a mention. Tempest is her usual clever self and her grandparents are a joy. We don't get to know the new characters well, but they worked fine for the story.
There are also a couple of recipes in the back that sound delicious. I haven't tried the yet though....