Preheat the oven to 350 degrees Fahrenheit. Spray a 9 x 4 x 3 loaf pan with nonstick cooking spray, then dust it well with flour and tap out the excess and set it aside.
Whisk together 1 cup all-purpose flour, 1 teaspoon ground cinnamon, ¼ teaspoon salt, and ¾ teaspoon baking soda in a medium bowl.
Add ¼ cup canola oil, ½ cup granulated sugar, ¼ cup packed light brown sugar, and 2 large eggs to a large bowl and beat with a hand mixer or a stand mixer fitted with the paddle attachment until combined. Add 1 teaspoon vanilla extract and ¼ cup sour cream and mix until fully combined.
Squeeze 1 ½ cups grated fresh zucchini with your hands to remove the excess liquid. You can use paper towels or cheesecloth to keep the zucchini contained. Stir the zucchini into the batter.
Add the flour mixture to the zucchini mixture and mix just until fully combined.
Add the batter to the prepared pan and bake for 50 to 60 minutes, or until a toothpick comes out clean from the center of the loaf.
Let it cool for about 10 minutes before removing the bread from the pan. Let it cool for at least 30 more minutes before slicing and serving.
