What is a forest pie?

"Forest pie" is not a recognized culinary term. It's possible you're thinking of:

* Forest fruit pie: This is a pie filled with a mixture of berries and other fruits common in forests, like blueberries, raspberries, blackberries, and wild strawberries.

* A pie inspired by the forest: This could be a pie with a filling that evokes the flavors and textures of the forest, such as a mushroom and wild herb pie, a pine nut and maple syrup pie, or a hazelnut and blackberry pie.

* A fictional pie: It's possible that "forest pie" is a term used in a book, movie, or other work of fiction.

Can you provide more context about where you encountered the term "forest pie"? This would help me understand what you're looking for.