• Preheat oven to 325°F.
• Lightly grease a 8.5 x 4.5” (1 pound) loaf pan (or grease and line with parchment paper).
• In a medium bowl, whisk together flour, both cocoa powders, baking soda, baking powder and salt. Set aside.
  1 cup all-purpose flour, ¼ cup Dutch process cocoa, ¼ cup unsweetened cocoa powder, ¼ teaspoon baking soda, ¼ teaspoon baking powder, ½ teaspoon salt
• In a small bowl, dissolve the espresso powder or instant coffee in the hot water. Stir until completely dissolved. Set aside.
  2 teaspoons espresso powder, 2 tablespoons hot water
• Add butter and sugar to the bowl of a stand mixer (or a large mixing bowl if using a hand mixer) and mix on medium high speed for approximately 5 minutes, scraping down the sides and bottom of the bowl regularly, until the mixture is very light in color and fluffy.
  1 cup unsalted butter, 1 cup granulated sugar
• Scrape down the bowl again and then add one egg at a time to the mixer on medium speed, making sure the egg is fully incorporated before adding the next egg. Scrape down the bowl with each additional egg.
  3 large eggs
• Add the sour cream, vanilla extract and espresso or coffee to the bowl and mix on medium-low speed until completely incorporated. Scrape down the bowl as needed.
  ⅔ cup sour cream, 2 teaspoons vanilla extract
• Add half of the the dry ingredients and mix on the lowest setting just until incorporated. Add remaining half and mix just until incorporated. Do NOT over mix. If you need to, use a spatula to fold in the flour mixture. Make sure the sides and bottom of the bowl have been scraped down during this process.
• Carefully transfer batter to the prepared loaf pan and bake for 50 to 65 minutes. Each oven is different. Check halfway through to make sure the cake isn't browning too quickly. If you see some dark spots, tent with foil.
• To determine when the cake is done, insert a skewer or toothpick into the thickest part of the cake. There should be a few moist crumbs on the skewer. Let cool in pan for 20 to 30 minutes before transferring to a wire cooling rack. Let cool before glazing.

Chocolate Glaze

• Place chocolate chips in a small heat proof bowl.
  ½ cup bittersweet chocolate chips
• Heat heavy cream in a microwave safe bowl on low heat in the microwave in 15 second increments until the cream just begins to simmer and bubbles form at the edges.
  ½ cup heavy cream
• Pour the hot cream over the chocolate chips and let sit for 5 minutes.
• Add the teaspoon of butter and vanilla extract and whisk until smooth and shiny. Allow to cool slightly, about 10 to 20 minutes. Drizzle the glaze over the top of the cake or serve with the glaze on the side.
  1 teaspoon butter, ½ teaspoon vanilla extract