Preheat your oven to 350 degrees Fahrenheit.
Grease a 9-inch springform pan with butter and dust with powdered sugar.
In a large bowl, cream together the sugar and softened butter.
Add the ricotta cheese and blend until light and fluffy, which should take 4 to 5 minutes.
Mix in the eggs one at a time, then add the egg yolk.
Stir in the vanilla extract, lemon zest, and lemon juice.
In a separate bowl, whisk together the all-purpose flour, baking powder, and salt.
Combine the wet and dry ingredients together until just blended.
Pour the batter into the prepared pan and smooth the top with a spatula.
Bake for 45 to 50 minutes or until a toothpick inserted into the center of the cake comes out clean.
Allow the cake to cool in the pan for 15 minutes before transferring it to a wire rack to cool completely.