Preheat the oven to 350°F. Line a 9-inch loaf pan with parchment paper then lightly grease it with cooking spray or butter.
In a medium bowl, whisk together the flour, cocoa powder and baking powder with 1/2 teaspoon kosher salt. Set the mixture aside.
Add the butter and sugar to the bowl of a stand mixer fitted with a paddle attachment. Cream the butter on medium speed until it is light and fluffy, about 2 minutes.
Beat in the eggs one at a time, beating between each addition, then beat in the vanilla extract.
Alternately beat in the dry mixture and the milk in intervals, scraping down the sides of the bowl as needed, then stir in the chocolate chips.
Scrape the batter into the prepared baking pan. Bake the cake until a toothpick inserted comes out clean, 50 to 55 minutes.
Remove the cake from the oven and let it cool completely. Remove it from the pan, dust it with powdered sugar, then slice and serve.