Preheat oven to 350 degrees. Grease and flour two standard-sized loaf pans. Beat together oil, eggs, sugar, and vanilla in a stand mixer. Add flour, cinnamon, baking soda, baking powder, and salt and mix until combined. The batter will be thick. Add zucchini and beat once more until incorporated.
In a small bowl, combine the topping ingredients. Pour half the batter into the prepared pans and sprinkle with half of the cinnamon sugar mixture. Cover with the remaining batter and sprinkle the remaining cinnamon and sugar mixture on top of each loaf.
Bake at 350 degrees for 45-50 minutes. Allow to cool before slicing.