Prepare Berries
Toss blueberries with sugar, lemon juice, and salt until syrupy.
Make Batter
Combine sugar and zest.
Whisk in flour, baking powder, and salt.
Stir in milk and melted butter.
Bake Cake
Spread batter in skillet.
Arrange berries and syrup over batter.
Pour boiling water over berries.
Bake 25-27 minutes at 220°C.
