Preheat your oven to 375 degrees F. This ensures that your cobbler bakes evenly and achieves that beautiful golden color.
In a large bowl, whisk together the granulated sugar, cornstarch, ground cinnamon, and a pinch of salt. This mixture will help sweeten and thicken the blueberry filling.
Add the fresh blueberries to the bowl and gently fold them into the sugar mixture using a spatula. Drizzle in the lemon juice and carefully mix until the berries are coated. This will enhance their flavor.
Transfer this berry mixture into an 8-inch square baking dish. If you don't have one, feel free to use a 9-inch deep-dish pie plate or a 10-inch cast iron skillet.
For the topping, in another large bowl, whisk together the all-purpose flour, the remaining granulated sugar, baking powder, and salt. This forms the dry base for your topping.
In a separate small bowl, combine the heavy cream, melted unsalted butter, and vanilla extract. Whisk these wet ingredients until smooth.
Pour the wet ingredients into the bowl with the dry ingredients and gently stir until just combined. Be careful not to overmix; you want to maintain a light texture.
Scoop the dough into 8 equal pieces and place them evenly over the blueberry filling. Make sure the pieces aren’t touching to allow for rising and spreading during baking.
Sprinkle the top with the remaining granulated sugar for an added sweetness and a lovely crust.
Place the baking dish into the preheated oven and bake for 35 to 45 minutes, or until the filling is bubbling and the topping is golden brown. Halfway through, rotate the pan for even cooking.
Once baked, transfer the pan to a wire rack and let it cool for at least 20 minutes. This cooling time helps set the filling. Serve warm or at room temperature.
Enjoy your delicious Blueberry Cobbler!