Preheat your oven to 350°F (175°C).
Grease a 9x5-inch loaf pan with butter or cooking spray.
In a large mixing bowl, whisk together the dry ingredients: flour, sugar, cocoa powder, baking powder, and salt.
In another bowl, mix the wet ingredients: melted butter, eggs, and vanilla extract until smooth.
Pour the wet ingredients into the dry ingredients and stir gently until just combined. Fold in the chocolate chips.
Pour the batter into the prepared loaf pan and drizzle hot fudge sauce over the top, swirling it in gently.
Bake for 30-35 minutes, checking for doneness with a toothpick.
Allow the brownie bread to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.