Cathy wowed us all recently with a deliciously moist chocolate cake containing... wait for it... green tomatoes! Although she sent me a photo of the recipe, it is kind of hard to read.
However, I was able to locate a recipe for Green Tomato Brownie Cake on a blog called Watching What I Eat. It seems to be based on the same recipe as Cathy's, but the good news is that the blogger, Vicki E., has reworked the traditional version into a far lighter one. Even better, the blog post includes both versions, so you can choose either the traditional cake, made with margarine, three eggs, and white sugar; or the lighter version made with just one egg, less sugar, and oil.
Here you go, just click this link to see both versions: http://watching-what-i-eat.blogspot.com/2012/10/green-tomato-brownie-cake-easy-tasty.html
And if you want to continue in the mystery cake mode, here is one made with beets and another that is a spice cake, rather than a chocolate one.
Mystery Chocolate Cake (made with beets): https://www.allrecipes.com/recipe/8049/mystery-chocolate-cake/
Green Tomato Cake (no chocolate): https://www.allrecipes.com/recipe/8381/green-tomato-cake/
Note: You will find links to all the knitting group's favorite recipes by clicking on the Recipes tab at the top of the blog under the header photo.