Preheat your oven to 350°F (175°C) and lightly grease or line a 9×5-inch loaf pan with parchment paper. In a medium bowl, sift together the all-purpose flour, cocoa powder, baking powder, baking soda, and salt. Set aside.
In a separate large bowl, whisk together the granulated sugar, eggs, and vanilla extract until smooth and well combined. Add the Greek yogurt, milk, and oil (olive or vegetable) and mix well.
Gradually add the dry ingredients to the wet mixture, stirring until just combined. Do not overmix. Gently fold in 1 cup of the chocolate chips or chunks into the batter, saving the remaining ¼ cup for topping.
Carefully pour in the hot water, stirring until the batter becomes smooth and slightly more liquid (this will help create a moist cake texture).
Pour the batter into the prepared loaf pan, smoothing the top with a spatula. Sprinkle the remaining ¼ cup of chocolate chips or chunks on top of the batter.
Place the loaf pan in the preheated oven and bake for 50-55 minutes, or until a toothpick inserted into the center comes out clean or with just a few crumbs attached.
Remove the cake from the oven and allow it to cool in the pan for 10 minutes. Then, transfer the cake to a cooling rack to cool completely. Slice and enjoy the rich, moist chocolate loaf cake!