Preheat the oven to 350 degrees . Butter two 9-inch round cake pans, line with parchment paper, then butter the paper. In a medium bowl, whisk together the flour, baking powder, baking soda and salt. In a small bowl, stir together the milk, lemon peel and lemon juice.
Using a hand-held mixer, beat the butter with 2 cups confectioners' sugar on medium speed until fluffy, 2 minutes. Add the whole eggs 1 at a time, beating after each addition. With the mixer on low speed, mix in half of the flour mixture, then the milk mixture, then the remaining flour mixture.
Divide the batter between the prepared cake pans and bake until springy to the touch, about 25 minutes. Let cool in the pans for 10 minutes, then turn out onto a rack and let cool completely.
Clean the mixer. Beat the remaining 1/2 cup confectioners' sugar and the egg whites. Place over a saucepan of barely simmering water and cook, whisking, until the confectioners' sugar dissolves and the mixture is hot to the touch, 2 to 3 minutes. Remove from the heat and beat on high speed until stiff, glossy peaks form and the mixture is cool, 7 to 10 minutes.
Peel the paper off 1 cake layer and place bottom side down on a cake plate. Spread one-third of the lemon curd on the cake and arrange the berries on top. Drizzle the remaining curd evenly over the berries. Peel the paper off the remaining cake layer and place upside down on the filling. Top the cake with the meringue.
Preheat the broiler to high. Broil the cake just until the meringue peaks are golden, about 2 minutes.