Begin by preheating your oven to 375°F (190°C) to ensure it’s hot and ready for baking.
In a large mixing bowl, gently combine the hulled and sliced strawberries, blueberries, and raspberries. Sprinkle 1/4 cup of the granulated sugar over the berries, then add the lemon juice and vanilla extract. Toss the mixture gently to ensure all the berries are well-coated, then set it aside to marinate for approximately 10 minutes.
In a separate mixing bowl, whisk together the all-purpose flour, baking powder, salt, and the remaining 1/4 cup of granulated sugar.
Gradually pour the melted butter and milk into the dry ingredients. Stir the mixture gently until it is just combined; it’s fine if it remains slightly lumpy.
Prepare a greased 9x9-inch baking dish by pouring the marinated berry mixture evenly across the bottom.
Carefully spoon the batter over the berries, aiming for an even distribution, but allow some berries to peek through.
To finish, sprinkle the top of the batter with brown sugar.
Bake the cobbler in the preheated oven for 35-40 minutes, or until the top transforms into a beautiful golden brown and a toothpick inserted into the center comes out clean.
After baking, remove the cobbler from the oven and let it cool slightly before serving warm.
Notes
For an exquisite touch, serve slices of the warm cobbler with a scoop of vanilla ice cream and garnish with fresh mint leaves.