Preheat oven to 350 degrees. Spray loaf pan with nonstick spray and line the bottom with parchment paper.
In a large bowl whisk together the flour, cocoa powder, baking soda, salt, granulated sugar and cinnamon.
In a smaller bowl, whisk the brown sugar with olive oil to combine. Add in the brewed coffee, vanilla and vinegar and whisk until smooth.
Add the wet ingredients to the dry ingredients and whisk until combined.
Pour the batter into the prepared loaf pan and bake for 50-55 minutes, or until top is springy to the touch and a toothpick in the center comes out clean.
Allow to cool completely, then dust with powdered sugar if desired.
Notes
I don't think you need the powdered sugar, but it does make it pretty!