What collaborations has Natasha Najjar engaged in within the vegan cookbook industry?

Summary

Based on the available content, Natasha Najjar has collaborated with her friend, Gianna Ciaramello, who is a vegan cookbook author. Gianna featured Natasha and other food bloggers in one of her cookbooks. Natasha contributed a vegan beef and broccoli recipe, which was one of her favorite dishes before she became a vegetarian. Gianna's book is called "Rabbit Food," and she also has another book called "The Mellow Cookbook."