Preheat the oven to 350˚F. Grease a 1-qt baking dish.
In a large mixing bowl, combine sugar, flour, and salt; set aside.
In another bowl, whisk together egg yolks, milk, lemon zest, and lemon juice. Pour the lemon mixture to the dry ingredients; mix well.
Beat the egg whites until a stiff peak forms. Add to the batter and fold them together. Pour the batter into a prepared baking dish.
Place the dish into a larger baking pan. Pour hot water into a large pan until it reaches half way up the size of the pan. Bake for 30 minutes or until the top gets golden brown.
Remove the dish from the pan and let cool for 5-10 minutes. Serve warm with fresh berries.