Delicious Blueberry Cobbler with Golden Biscuit Topping

Ingredients

• 4 cups (600 g) fresh blueberries, or frozen blueberries kept frozen
• 1/2 cup (100 g) granulated sugar
• 1 1/2 tablespoons cornstarch
• 1 tablespoon fresh lemon juice
• 1 teaspoon finely grated lemon zest
• 1 teaspoon vanilla extract
• 1/4 teaspoon fine salt
• 1 tablespoon unsalted butter, for dotting the filling
• Butter, for greasing the baking dish
• 1 1/2 cups (190 g) all-purpose flour
• 1/4 cup (50 g) granulated sugar, plus 1 tablespoon for sprinkling
• 2 teaspoons baking powder
• 1/2 teaspoon fine salt
• 6 tablespoons (85 g) cold unsalted butter, cut into small cubes
• 3/4 cup (180 ml) cold buttermilk
• 1/2 teaspoon vanilla extract
• Vanilla ice cream or whipped cream, optional