Preheat the oven to 325 degrees F. Spray a 9×5-inch loaf pan with nonstick spray.
In a small bowl, whisk together the flour, salt, baking soda, powder and cinnamon. In a large bowl, whisk together the eggs, olive oil, sugar and vanilla extract. Slowly add the dry ingredients to the wet and mix until the batter is smooth. Stir in the grated zucchini.
Spread half of the batter in the bottom of the loaf pan. Sprinkle the top with the filling mixture, then add the remaining batter on top. If needed, you can spray the back of a spoon with nonstick spray and spread out the top layer.
Top the cake with the streusel mixture. Bake for 60 to 70 minutes, or until the center of the cake is no longer jiggly. Let cool completely (yeah… right) before slicing (or cutting)!