01 -
Preheat the oven to 175°C and grease a 23-centimeter round cake tin.
02 -
In a medium mixing bowl, whisk together flour, cocoa powder, baking powder, baking soda, and salt until uniformly blended.
03 -
In a large mixing bowl, beat unsalted butter and granulated sugar until light and fluffy.
04 -
Incorporate eggs one at a time into the creamed mixture, then blend in ricotta cheese, milk, and vanilla extract until smooth.
05 -
Gradually fold the dry ingredients into the wet mixture until just combined to avoid overmixing.
06 -
Gently fold semi-sweet chocolate chips into the batter.
07 -
Pour half of the batter into the prepared cake tin. Add remaining cocoa powder to the other half and stir until homogenized.
08 -
Drop spoonfuls of the chocolate batter over the plain batter in the cake tin, then use a knife to swirl and create a marble effect.
09 -
Bake for 35 to 40 minutes, or until a skewer inserted in the center emerges clean.
10 -
Allow the cake to cool in the tin for 10 minutes, then transfer to a wire rack to cool completely before cutting.