Preheat oven to 350 degrees F.
Grease a 9x9 square baking pan with butter flavored cooking spray.
In a blender, puree the cooked and rinsed black beans with the safflower and olive oil.
Pour into the bowl of an electric mixer.
Add eggs, cocoa, sucanat, truvia and vanilla.
Melt half the chocolate chips and add to mixer.
Blend on medium until smooth.
In a small bowl, whisk together oat flour, baking powder and salt.
Add to the mixer until just incorporated.
Stir in remaining chocolate chips.
Pour into prepared pan and bake for about 20 minutes, until surface looks somewhat matte around the edges and shiny in the middle.
Let cool at least 15 minutes before cutting.
Dust with powdered sugar and serve.