Preheat oven to 350°. Spray 2 (9- by 5-inch) loaf pans with coconut oil cooking spray.
In a medium bowl, mix flours, baking soda, baking powder, salt, parsley, garlic powder and rosemary until well combined, then set aside. In a larger bowl, add eggs, milk, yogurt and olive oil; mix until thoroughly combined. Add zucchini and scallions and mix until incorporated. Carefully stir in flour mixture until just combined. Don’t over mix. Divide batter evenly between loaf pans.
Bake for 30–40 minutes, or until a toothpick inserted in the center comes out clean.
Let cool in loaf pan for 10 minutes, then carefully remove from pans and place on a cooling rack. Slice and serve warm with whipped butter.