Preheat the oven to 350°F:
Spray an 8 1/2 x 4 1/2-inch loaf pan with nonstick cooking spray. Line the pan with parchment paper, leaving a 2-inch overhang on two of the sides. Set it aside.
Melt the chocolate with espresso powder in boiling water:
Place the espresso powder and 3/4 cup (163g) chocolate chips in a large bowl. Pour in the boiling water and let it sit for 5 minutes. Then, whisk together until smooth.
Add the wet ingredients:
Whisk in the brown sugar, melted butter, vegetable oil, and vanilla until smooth. Add the eggs and whisk until fully combined.
Mix the dry ingredients:
Set a sifter or fine mesh sieve over a medium bowl. Add the flour, cocoa powder, baking soda, and salt, and sift. Whisk to combine.
Combine the wet and dry ingredients:
Use a rubber spatula to fold the flour mixture into the chocolate mixture until just combined.
Add chocolate chips:
Fold in the remaining 3/4 cup (163g) chocolate chips.
Bake the pound cake:
Scrape the batter into the prepared loaf pan. Bake until the loaf has risen and cracked a bit on the top, 65 to 75 minutes. A toothpick inserted into the center should come out with just a few moist crumbs, but no wet batter.
Cool and serve the pound cake:
Remove the pan from the oven and set it on a wire rack to cool for about 1 hour. Use the parchment sling to lift the loaf out. Slice and serve at room temperature.
