Prep Your Zucchini: First things first, grab your grated zucchini. This is a crucial step: place the grated zucchini in a fine-mesh sieve or wrap it in a clean kitchen towel and squeeze out as much excess moisture as you possibly can. Seriously, squeeze it like your life depends on it! Too much water makes for a gummy cake.
Get the Oven Ready: Preheat your oven to 350°F (175°C). Grease and flour or line an 8 or 9-inch square baking pan or a loaf pan with parchment paper.
Mix the Dry Stuff: In a large bowl, whisk together the flour, granulated sugar, baking powder, cinnamon, and salt. Give it a good mix to make sure everything is evenly distributed.
Combine the Wet Stuff: In a separate medium bowl, whisk together the egg, brown sugar, vegetable oil, melted butter, and milk until well combined.
Bring It All Together: Pour the wet ingredients into the bowl with the dry ingredients. Stir with a spatula or wooden spoon just until combined. Be careful not to overmix – a few streaks of flour are okay!
Fold in Zucchini: Gently fold in the squeezed, grated zucchini. Make sure it's evenly distributed throughout the batter.
Pour and Bake: Pour the batter into your prepared pan and spread it evenly. Pop it in the preheated oven.
Bake Time: Bake for 40-50 minutes, or until a wooden skewer or toothpick inserted into the center comes out clean. If using a loaf pan, it might take a little longer, maybe 50-60 minutes.
Cool: Let the cake cool in the pan for about 10-15 minutes before carefully transferring it to a wire rack to cool completely. Or, if you're impatient like me sometimes, just let it cool mostly in the pan before slicing!