Mix the following in a large bowl: 3 cups flour, one egg, a teaspoon and a half of vinegar, three spoons of ground cinnamon, two spoons of vanilla essence, a cup of melted butter, a little more than a cup of sugar, a spoon of baking soda and a tiny pinch of salt. I mixed all of it with my hand. Preheat oven to 190C. Roll cookie dough into 22-24 balls. Pour out some cinnamon sugar in a small bowl. Roll each ball in the cinnamon sugar. Bake on a cookie sheet for 10 minutes. When you take them out of the oven, they'll be soft. Use the back of a glass to flatten them a little, and then let them cool.
Leave some out for Santa!