Chocolate Caramel Slice

First make the sweetened condensed soy milk. This can be made the night before, if you like. In a medium saucepan melt 3 Tablespoons margarine on low heat. Add sugar, vanilla and salt and stir until sugar has dissolved. Add powdered soy milk and boiling water and whisk vigorously until no lumps remain. Chill in fridge until ready to use.
Preheat oven to 180 degrees C (350 degrees F). Grease a 20cm square brownie tin and line with baking paper.
To make the base sift the flour in a medium bowl, and the brown sugar, coconut and 1/3 cup melted margarine and mix until well combined. Press into the prepared tin and bake for approx 10 minutes, until base has risen and slightly browned. Allow to cool while making the caramel.
In a medium saucepan melt an 1/8 of a cup of margarine and golden syrup. Add the condensed soy milk mixture and cook over low heat for approx 8 minutes. Place 2 Tablespoon cornstarch in a small bowl, add a few spoonfuls of the caramel mixture and mix until cornstarch is dissolved. Add this back into the saucepan of caramel and heat, stirring constantly until mixture thickens (be careful to scrap the bottom of the saucepan cos the mixture tends to stick there). The mixture should be very thick. If it hasn't thickened enough repeat the procedure with another Tablespoon of cornstarch. Once the caramel is done pour over the base and bake for another 10-12 minutes, until the edges of the caramel are slightly browned. Let the slice cool to room temperature.
Once slice has fully cooled, melt the chocolate in your preferred method, taking care not to burn. Pour evenly over the slice and place in the fridge to set for at least an hour. Check the slice every 10 minutes or so and when the chocolate is still soft but cool enough to keep it's shape, run a knife just through the chocolate layer in the sizes that you would like your slices to be (I suggest small squares as it's very rich). This will stop the chocolate layer from cracking when you try to slice it later. After an hour you can cut the slice to your desired size, and store in a tightly sealed container in the fridge.