For The Biscuit Layer For The Caramel Layer For The Chocolate Layer

1. Combine the ingredients for the biscuit layer in a bowl and mix until well combined.
2. Line a 20cm square baking tin with parchment paper and press the biscuit mixture firmly into the base to create a thin layer. Ensure the mixture is pressed evenly to the edges and corners for a neat finish.
3. Refrigerate the baking tin to firm up the biscuit layer while you prepare the caramel. The coconut oil in the mixture should cause it to set quickly.
4. Blend the caramel ingredients in a blender for 2-3 minutes until smooth. The caramel will change color and texture as it blends, transitioning from a light color and grainy texture to a deep gold, sticky, and smooth consistency.
5. Spread the caramel evenly over the firm shortbread base in the tin. Return the tin to the freezer to set for 30 minutes.
6. Simmer a small saucepan of water and place a bowl on top to create a 'bain-marie'. Add the chocolate and dairy-free milk to the bowl and allow it to melt gently.
7. Stir the melted chocolate and milk until glossy and fully combined.
8. Pour the melted chocolate over the partially frozen caramel layer and spread it out using a palette knife or spoon.
9. Refrigerate the tin again to set the chocolate layer for 30 minutes.
10. Remove the Millionaire's Shortbread from the baking tin and place it on a chopping board. Dip a large knife in hot water, wipe it, and slice the shortbread into 12 large squares or 24 bite-size fingers.
11. Store the shortbreads in the refrigerator if you intend to consume them within the next few days. Alternatively, you can freeze the sliced shortbreads for later use.