Pre-heat oven to 180°C/ 160°C fan assisted / gas mark 4 / 350°F and line and grease a 20cm (8 inch) square baking tin.
In a large mixing bowl whisk together the sugar, flours, oats, ginger, baking powder, bicarbonate of soda and salt and set aside for a minute.
Take a medium sized saucepan and pour in the almond milk, golden syrup and coconut oil. Turn onto a gentle heat and stir the ingredients together until everything has melted together.
Pour the wet ingredients, along with the apple cider vinegar into the dry ingredients, along with the stem ginger and beat well with a wooden spoon.
Pour the mixture into the baking tin and bake for 40 minutes.
Remove from the oven, leave the parkin to settle for ten minutes then carefully turn out onto a wire rack to cool completely.
Make the icing by beating together the lemon juice and zest with the icing sugar until the icing is pourable.
Pour the icing over the cooled parkin and sprinkle over the extra diced stem ginger. Leave to set and then cut the parkin into 12 squares.