PLEASE NOTE: This is not a sweet treat. It is only sweetened slightly by the bananas and mostly by the chocolate drizzle on top. If you do want to sweeten it up a bit more, I recommend adding 1/4 cup maple syrup or honey when you're mixing in the eggs!
Preheat your oven to 350℉. Lightly spray or grease a 10½ x 7½" baking dish.
In a medium bowl, mix the oats and the milk and let it sit for 10 minutes.
In a large bowl, mash your bananas and then whisk in the eggs and salt. Next mix in the cacao powder and baking powder until combined. Lastly milky oats to the large bowl and mix to combine. Transfer the batter to your baking dish. Sprinkle on the chopped cashews and bake for 30-35 minutes or until a toothpick comes out clean.
Let the cake cool for 20 minutes then melt the chocolate with the oil in a small pot on low heat, stirring constantly. Drizzle it over the cake and let it set in the fridge or on your counter. Slice and serve.