To prepare a zucchini peanut and oatmeal cookies baked goods recipe, you will first need to prepare your zucchini. Cut the zucchini in half lengthwise and scoop out the seeds. Peel the skins and cut the flesh into small cubes. Add the cubed flesh to the dry ingredients and mix until the ingredients are well combined. Pour the wet ingredients into the egg yolk mixture and stir to combine. Sift the flour, baking powder, salt, and baking soda together. Stir in the oat mixture. Bake the cookies for 20 minutes at 375 degrees F. Remove from the oven and let cool for 5 minutes before transferring to wire racks to cool completely.