In a small mixing bowl cream the butter into the sugar until light and fluffy.
Add the ginger and cocoa powder and mix again.
Beat in the eggs (one at a time) adding a little flour as you go.
Fold in the remaining flour and then add the milk.
Remove ¾ of your mixture and put to one side. Pour the caramel sauce over the remaining mixture that is still in the bowl and then add the rest of the mixture over the top. This will then give it that toffee centre.
In your Instant Pot place the usual 180ml of water into the bottom, followed by your steaming shelf, followed by your mixing bowl that should fit easily on the shelf.
Place the lid on your Instant Pot and set the valve to sealing.
Cook for 15 minutes on the steam function and then leave it to rest for 5 minutes before serving.