Preheat the oven to 375F/180C and line a 9x9-inch baking dish with parchment paper.
Stir together the oats, sugar, baking powder, salt and chocolate (and instant coffee if using).
In another bowl whisk together the milk, egg, and vanilla extract.
Pour the wet ingredients to the dry ones and stir until combined.
Stir in the cream cheese. Break it apart with a spoon whilst still leaving in a few chunks in there.
Pour into the baking dish and bake for 23-25 minutes, or until just set - serve immediately.