Whisk together the flour, baking soda, spices, and salt. Set aside.
Whisk together the butter, sugar, black treacle, and egg until combined. Add the dry ingredients, and fold in until completely combined.
Roll the dough into 0.5oz balls (the dough will be very soft), and place them onto the prepared baking tray. Bake for 10 - 12 minutes. Allow to cool for 5 minutes before transferring them to a wire rack to cool completely.
*Light or true molasses is much sweeter than blackstrap molasses (which is very bitter), and is much preferred in baking.
Cookies stay fresh, in an airtight container, at room temperature for up to 1 week.
Cookie dough balls can be kept in the fridge for up to 5 days, or frozen for up to 3 months. Bake from frozen for an extra minute.
The calories are an estimate only.