How to Make It
Preheat oven to 350°F. Lightly grease a 9x13 baking dish with butter or nonstick spray.
Make the base: Whisk together eggs and sugar in a large bowl until evenly combined. Add ricotta, lemon zest and juice, cream, flour, and salt and whisk to combine; pour into prepared baking dish.
Make the cake mix: Whisk flour, sugar, baking powder, baking soda, and salt in a medium bowl and sprinkle evenly over the base. Using the largest holes on a box grater, grate the butter evenly over the surface of the cake.
Bake until cake is puffed and golden brown, 35 to 40 minutes. Cool 30 minutes before serving.