Step 1: Get Your Oven Ready: First things first, preheat your oven to a cozy 350°F (175°C). Then, grab an 8-inch or 9-inch square baking pan and lightly grease it. This helps ensure your beautiful cake slides out easily.
Step 2: Whip Up the Cake Batter: In a medium-sized bowl, let's mix all our dry ingredients for the cake. Whisk together the flour, baking powder, salt, and that wonderful cinnamon until they're all friendly with each other. In a larger bowl, it’s time for the wet ingredients. Stir together the granulated sugar, vegetable oil, and egg until they're smooth and well combined. Now, pour in the milk. Add the dry ingredients to your wet mixture and mix gently until everything is just combined. Overmixing is a no-no when it comes to tender cakes! Finally, and this is the fun part, gently fold in the shredded zucchini. It will feel like a lot, but trust me, it’s what makes this cake so wonderfully moist.
Step 3: Craft the Crumb Topping: Grab a small bowl for this delightful streusel. Toss in the packed brown sugar, a tablespoon of flour, and another teaspoon of cinnamon. Pour in the melted butter and stir everything together with a fork or your fingers until the mixture is beautifully crumbly. This is the magic dust that takes our coffee cake from great to absolutely divine!
Step 4: Assemble and Bake: Pour your lovely cake batter into the prepared pan and spread it out evenly. Now for the grand finale: sprinkle that glorious crumb topping all over the batter. Make sure to get an even layer of that buttery, cinnamon goodness. Pop it into your preheated oven and bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean. Every oven is a little different, so keep an eye on it!
Step 5: Cool and Serve: Once baked to golden perfection, take the cake out of the oven. Let it cool in the pan on a wire rack for at least 15 minutes. This gives it a chance to set up nicely before you slice into that irresistible goodness. Then, slice, serve, and enjoy every single comforting bite!