Preheat the oven to 325°F (165°C).
Prepare the Zucchini: Press or drain the excess moisture out of the zucchini shreds.
Mix Cake Ingredients: Combine the cake ingredients in the order given until well incorporated.
Prepare the Topping: In a bowl, combine the topping ingredients with your fingers or in a food processor to achieve a crumbly texture.
Layer the Cake: Pour half of the batter into a greased 9×13 cake pan. Sprinkle half of the crumbs on top. Repeat the process with the remaining batter and topping.
Bake: Place in the oven and bake for 45 minutes. The top should be crunchy and textured, and the cake should bounce back when you gently press it.
