Preheat the oven to 350 degrees. Grease two loaf pans (you can also make these as muffins, the recipe will make 24).
Cream butter and sugar together (I do this in a stand mixer, but you can use a hand mixer or just a wooden spoon). Add in applesauce, beaten eggs, grated zucchini and vanilla and mix to combine.
In a separate bowl, mix together all the dry ingredients and then stir them into the wet ingredients in three batches.
Add in the nuts and stir to incorporate.
Divide between the two loaf pans and bake for 45-50 minutes****, until a skewer comes out clean and the tops are nice and brown. It is good plain, or toasted and spread with butter and jam.