Preheat the oven to 325°F (160°C) and line one large baking tray with a Silpat mat or parchment paper.
Combine all dry ingredients in a mixing bowl.
Using a hand mixer, combine all the wet ingredients in a separate bowl.
Mix the ingredients until a sticky dough develops by pouring the wet ingredients over the dry ones.
Make a large ball out of the dough using a silicone spatula.
Take a small amount of dough, form it into a ball between your palms, and set it on the baking sheet that has been lined with parchment paper. Repeat the process with the leftover dough, (you should get about 8-10 balls). Create a gap between each ball as you arrange the balls on the tray.
After transferring, bake for 12 to 15 minutes in the preheated oven. After cooling, they will become crisp on the outside and chewy on the inside. When they first come out of the oven, they will appear a little squishy. So, give the cookies about 10 minutes to cool before removing them from the baking sheet.
Add 2 candy eyes to each cookie, then drizzle with white chocolate. Refrigerate for a few minutes to set.
Use pure melted butter and brown sugar to create chewy, soft chocolate cookies. These will result in an easily workable dough, which is necessary for that purpose.
Plain all-purpose flour or self-raising flour can be used in place of oat flour. If you choose plain flour, you must add a rising agent of some kind.
You can use white, dark, or milk chocolate to decorate these homemade Halloween cookies, or you can choose to make them plain.