Preheat the oven to 350°F. Prepare an 8x8 pan by either greasing it or lining it with parchment paper.
Add oats to a blender or food processor. Pulse until you have a smooth flour-like consistency. Remove from the blender.
In the blender, add together the black beans (drained), brewed coffee, maple syrup, melted coconut oil, 2 egg yolks, and vanilla extract. Blend until quite smooth.
Add the oat flour you just made, salt, baking powder and cocoa powder to the blender and blend again.
Add the batter to the brownie pan, stir in chocolate chips with a spoon and smooth out the top.
In a separate small bowl, stir together peanut butter, maple syrup, and a pinch of sea salt.
Make 9 small dollops of the peanut mixture on the top of your brownie batter.
With the end of a chopstick or a similar kitchen tool swirl the peanut butter through the brownie batter to create a beautiful swirl pattern.
Bake for 20 minutes and allow to cool completely.