Preheat the oven to 350F/176C. Line a baking tray with parchment paper, or a silicone mat.
In a medium bowl, whisk together the flour, baking soda, ginger, cinnamon, nutmeg, and salt. Set aside.
In a separate bowl, mix together the sugar, oil, molasses, egg, and vanilla until combined. Add in the dry ingredients, and mix until just combined.
Roll the dough into 18 small balls (the dough may be a little sticky, damp your hands with warm water to make it more manageable). Fill a small bowl with granulated sugar, and roll each ball in the sugar until it is completely coated. Place the balls on the prepared baking tray, about 2 inches apart. Bake for 8 - 10 minutes, until the cookies start to crack on top. Let cool for 5 minutes before transferring the cookies to a wire rack to cool completely.
In a microwave-safe bowl, add the chocolate chips. Microwave on high in 10 second intervals, stirring between intervals, until melted.
Dip half of a cooled cookie in the melted chocolate, then place on baking paper, and leave to set. Repeat with all the cookies.