Preheat the oven to 350°F. Grease and flour a 9x13-inch baking pan. Line the bottom of the pan with parchment paper and lightly grease the paper.
In a medium bowl, add the flour, baking powder, baking soda, and salt together. Mix until well combined and set aside.
In a mixer, add the butter and sugar together. Beat until it is light and fluffy. Beat in the eggs one at a time, beating well between each egg. Beat in the vanilla and mix for about a minute longer.
Begin to add the flour mixture and the buttermilk. Alternate between the two, starting with the flour, which should be added in three additions, and the buttermilk, which should be mixed in two additions. When you add the last bit of flour, mix until just combined.
Pour the batter into the baking pan and evenly spread the batter throughout the pan.
Bake the cake for 35-40 minutes, or until a toothpick inserted in the middle comes out clean. If the cake is still not finished, but the top is browning too fast, carefully cover with aluminum foil.
Remove the finished cake and allow to cool completely.
While the cake is cooling, mix together the ingredients for the filling. Take the cooled cake and use the bottom of a wooden spoon to create holes in the cake.
Pour the mixture into the cake holes, reserving about 1/3 of the filling.
Make the topping by beating the whipping cream until it forms stiff peaks. Fold in the remaining ricotta filling. Alternatively, you can add the filling to the whipping cream and beat until it forms medium peaks. (I prefer the first method, as you do not always need the remaining filling to get the flavor to come through in the topping.)
Spread the topping over the cake and sprinkle with more mini chocolate chips.