- Preheat oven to 375°F. Grease a 9- x 13-inch pan baking dish with extra virgin olive oil.
- Heat oil over medium heat in a large sauté pan. Sauté leeks until translucent, about 4 minutes. Add mushrooms, salt and pepper and cook for 10 minutes, until softened. Add garlic and cook an additional 3 minutes.
- In a large mixing bowl, whisk eggs, broth, parsley, and soy sauce.
- Add challah and mushroom mixture and mix well. Place in the prepared baking dish and drizzle with sesame oil.
- Bake at 375°F, covered, for 40 minutes. Uncover and bake 15 minutes more until browned.