Step 1

Preheat oven to 350°F (176°C) and lightly grease a 9" x 5" loaf pan.

Step 2

Grate the zucchini using the large holes of a cheese grater. Place it in a colander and squeeze out excess moisture. Leave the zucchini in the colander while you mix the remaining ingredients.

Step 3

In a large bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon and chopped walnuts. Set aside.

Step 4

In a separate bowl, mix the light brown sugar, eggs, sourdough starter discard, vanilla extract and oil with a spatula until smooth. Pour the dry ingredients into the wet ingredients and mix until just combined. Stir in the grated zucchini.

Step 5

Pour the batter into the greased baking pan and bake for 55-60 minutes, or until a toothpick inserted in the center comes out clean. (See notes)

Step 6

Let the bread cool for 10-15 minutes before transferring it to a cooling rack. Slice and serve.