Peel and chop the zucchini into bite-sized pieces. Add the chopped zucchini, butter, and cinnamon sticks to a pan. Cover with the lid and cook for 20 minutes over medium-low heat. Remove the lid and continue to cook over low heat until all the liquid evaporates.
Step 2
Remove the cinnamon sticks from the pan. Add the lemon juice, ½ teaspoon of apple extract, and erythritol. Taste and optionally add some more sweetener. Using a potato masher, mash the mixture until completely smooth. Optionally, transfer the mixture to a blender and blend until smooth.
Step 3
Refrigerate the apple sauce for about an hour before serving. The consistency changes as the applesauce cools. Serve or store for later.