Preheat the oven to 350 degrees F and line a 9x9 inch square pan with parchment paper.
In a medium bowl, combine the cocoa powders, chocolate, and hot coffee together. If the chocolate does not fully melt, heat in the microwave in 20 second intervals until fully melted.
In a large bowl, whisk together the flour, sugars, espresso powder, baking powder, and salt.
To the dry ingredients, add the oil, milk, yogurt, eggs and vanilla. Whisk until fully combined.
Add in the chocolate mixture and whisk until fully combined.
Pour the batter into the prepared pan and bake for 20-25 minutes or until a toothpick inserted comes out clean.
Allow cake to cool in the pan for a few minutes before removing to cool completely on a wire rack.
For the peanut butter frosting:
In the bowl of a stand mixer fitted with a paddle attachment, cream the butter until smooth.
Add the peanut butter and mix until fully combined.
While mixing on low speed, slowly add the powdered sugar.
Turn the speed up to medium, then add the salt and the heavy cream and beat until smooth.
Frost the cake as desired and enjoy!
Notes
Use any neutral oil, such as light tasting olive oil, canola oil, or vegetable oil.
I recommend only using a thick, creamy peanut butter like Jif or Skippy.
Store this cake in an air-tight container at room temperature for up to three days.