Preheat oven to 350°F and grease a 9x13-inch baking dish.

In a large bowl, mix together cake mix, water, oil, and 3 eggs until smooth.

In a separate bowl, combine ricotta, 4 eggs, sugar, and vanilla extract.

Pour cake batter into baking dish, then spoon ricotta mixture on top.

Bake for 55–60 minutes, or until a toothpick inserted comes out clean. Cool completely.

In another bowl, whisk pudding mix and cold milk for 2–3 minutes until thickened.

Fold in whipped topping gently until smooth. Spread evenly over cooled cake.

Refrigerate for at least 1 hour before serving.