Preheat the oven to 350 degrees F (175 degrees C). Lightly grease a 9x13-inch pan.

Prepare the cake mix according to package directions, including any eggs, oil, and water called for on the box. Pour batter into the prepared pan.

Mix ricotta cheese, sugar, eggs and vanilla extract together; spoon over cake batter.

Bake in the preheated oven for about 45 minutes. Sprinkle cake with confectioners' sugar when cool.