Ingredients
Method
Step-by-Step
- Heat the oven to 350°F (175°C) and grease an 8-inch square baking dish or a comparable 1 1/2- to 2-quart baking dish.
- Whisk together the flour, baking powder, and salt in one bowl. In a separate bowl, whisk the sugar, melted butter, milk, egg, lemon zest, and lemon juice until combined.
- Add the dry ingredients to the wet ingredients and stir just until no dry flour remains. Fold in the blueberries gently, then spread the batter in the prepared dish.
- Mix the topping sugar, flour, and cornstarch, then sprinkle it evenly over the batter. Slowly pour the boiling water over the entire surface without stirring.
- Bake for 40–50 minutes, until the top is golden and set while the center still has a slight, soft jiggle. Let the cake stand for 10–15 minutes before serving.
- Spoon the cake into bowls so the lemon-blueberry sauce underneath comes up over the top. Serve warm with vanilla ice cream, whipped cream, or lightly sweetened yogurt.
Notes
Use fresh lemon zest as well as juice for the strongest lemon aroma. Add frozen blueberries while still frozen, not thawed, to avoid excess liquid. Pour the boiling water slowly and do not stir. A shallow baking dish helps the top set evenly before the sauce overcooks.
