Preheat the oven to 180C degrees (356F).
In a bowl, combine the baking powder and salt with the flour, mix, and set aside.
In another, mash the ricotta cheese with a fork and then add icing sugar. Stir quickly before adding eggs. Beat with electric whips until smooth.
Add cocoa, flour, and yogurt, stirring quickly with a metal spoon before blending the mixture with the electric whips.
Add chocolate chips and mix with a metal spoon.
Line a mold with moistened and squeezed baking paper, pour the mixture into the mold, and bake in the preheated oven for about 35 minutes.
Remove from oven, let cool, and dust with powdered sugar.
The cake will keep fresh, out of the refrigerator, for several days.