Preheat the oven to 350ºF or 180ºC. Line a 9×5-inch (23×13 cm) loaf pan with parchment paper or grease it with some oil (I always use coconut oil).
Mix the plant milk and vinegar in a jar or bowl until well combined. Let the mixture rest at room temperature for at least 5 minutes. After this time, the milk will thicken and curdle.
In the meantime, add the dry ingredients to a large mixing bowl (flour, sugar, baking powder, cinnamon, and salt) and mix until combined.
Add the oil, vanilla extract, and the plant milk and vinegar mixture. Stir until well combined.
Incorporate the grated zucchini and the walnutsand stir again until well combined.
Add the batter to the pan and bake for 50 to 60 minutes (my zucchini bread was ready in 60 minutes). Stick a toothpick into the center of the loaf and if it comes out clean, the loaf is done. Cover the top with foil if the bread gets browned but the middle isn’t done yet.
Let it cool for 15 minutes before transferring it to a cooling rack and then let it cool completely. If you don’t have a cooling rack, just use a dish or what you have on hand. You can also enjoy it warm if you want, though.