Preheat your oven to 350°F (175°C). Grease and flour a 9x5-inch loaf pan.
In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and cocoa powder. Set aside.
In a large mixing bowl, cream the softened butter and sugar together until light and fluffy, about 3-4 minutes.
Add the ricotta cheese, eggs, and vanilla extract to the butter mixture, mixing until well combined.
Gradually add the dry ingredients to the wet ingredients, mixing just until combined. Do not overmix.
Gently fold in the chocolate chips.
Pour half of the batter into the prepared loaf pan. Use a spatula to smooth it out.
Add the remaining batter on top and swirl it gently with a knife to create a marbled effect.
Bake for 50-60 minutes, or until a toothpick inserted into the center comes out clean.
Allow the cake to cool in the pan for 10 minutes, then transfer it to a wire rack to cool completely.